From 9630918965de3e090a73553fbde753251159938c Mon Sep 17 00:00:00 2001 From: Michael Snyder Date: Thu, 20 Apr 2006 23:18:48 +0000 Subject: [PATCH] 2006-04-20 Michael Snyder * 2006-03-22 Jim Blandy Add support for the Renesas M32C and M16C. * configure.tgt (m32c-*-*): New entry. * config/m32c/m32c.mt: New file. * m32c-tdep.c: New file. * Makefile.in (elf_m32c_h): New variable. (m32c-tdep.o): New rule. * NEWS: Mention new target. * MAINTAINERS: Designate Jim Blandy as responsible maintainer. --- gdb/MAINTAINERS | 3 + gdb/Makefile.in | 7 + gdb/NEWS | 6 + gdb/config/m32c/m32c.mt | 7 + gdb/configure.tgt | 2 + gdb/m32c-tdep.c | 2552 +++++++++++++++++++++++++++++++++++++++ 6 files changed, 2577 insertions(+) create mode 100644 gdb/config/m32c/m32c.mt create mode 100644 gdb/m32c-tdep.c diff --git a/gdb/MAINTAINERS b/gdb/MAINTAINERS index dbd2f9368b..48f8c00159 100644 --- a/gdb/MAINTAINERS +++ b/gdb/MAINTAINERS @@ -266,6 +266,9 @@ the native maintainer when resolving ABI issues. ia64 --target=ia64-linux-gnu ,-Werror (--target=ia64-elf broken) + m32c --target=m32c-elf ,-Werror + Jim Blandy, jimb@codesourcery.com + m32r --target=m32r-elf ,-Werror m68hc11 --target=m68hc11-elf ,-Werror , diff --git a/gdb/Makefile.in b/gdb/Makefile.in index beab57cd73..f96c20cfe7 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -582,6 +582,7 @@ elf_sh_h = $(INCLUDE_DIR)/elf/sh.h elf_arm_h = $(INCLUDE_DIR)/elf/arm.h $(elf_reloc_macros_h) elf_bfd_h = $(BFD_SRC)/elf-bfd.h elf_frv_h = $(INCLUDE_DIR)/elf/frv.h $(elf_reloc_macros_h) +elf_m32c_h = $(INCLUDE_DIR)/elf/m32c.h $(elf_reloc_macros_h) libaout_h = $(BFD_SRC)/libaout.h libiberty_h = $(INCLUDE_DIR)/libiberty.h libbfd_h = $(BFD_SRC)/libbfd.h @@ -598,6 +599,7 @@ gdb_callback_h = $(INCLUDE_DIR)/gdb/callback.h gdb_sim_arm_h = $(INCLUDE_DIR)/gdb/sim-arm.h gdb_sim_d10v_h = $(INCLUDE_DIR)/gdb/sim-d10v.h gdb_sim_frv_h = $(INCLUDE_DIR)/gdb/sim-frv.h +gdb_sim_m32c_h = $(INCLUDE_DIR)/gdb/sim-m32c.h gdb_sim_ppc_h = $(INCLUDE_DIR)/gdb/sim-ppc.h gdb_sim_sh_h = $(INCLUDE_DIR)/gdb/sim-sh.h splay_tree_h = $(INCLUDE_DIR)/splay-tree.h @@ -2215,6 +2217,11 @@ m2-typeprint.o: m2-typeprint.c $(defs_h) $(bfd_h) $(symtab_h) $(gdbtypes_h) \ $(expression_h) $(value_h) $(gdbcore_h) $(target_h) $(m2_lang_h) m2-valprint.o: m2-valprint.c $(defs_h) $(symtab_h) $(gdbtypes_h) \ $(m2_lang_h) $(c_lang_h) +m32c-tdep.o: m32c-tdep.c $(defs_h) $(gdb_assert_h) $(elf_bfd_h) \ + $(elf_m32c_h) $(gdb_sim_m32c_h) $(dis_asm_h) $(gdbtypes_h) \ + $(regcache_h) $(arch_utils_h) $(frame_h) $(frame_unwind_h) \ + $(dwarf2_frame_h) $(dwarf2expr_h) $(symtab_h) $(gdbcore_h) \ + $(value_h) $(reggroups_h) $(prologue_value_h) $(target_h) m32r-linux-nat.o: m32r-linux-nat.c $(defs_h) $(inferior_h) $(gdbcore_h) \ $(regcache_h) $(linux_nat_h) $(gdb_assert_h) $(gdb_string_h) \ $(gregset_h) $(m32r_tdep_h) $(target_h) diff --git a/gdb/NEWS b/gdb/NEWS index 526f45a43d..bf6f31e1ea 100644 --- a/gdb/NEWS +++ b/gdb/NEWS @@ -3,6 +3,12 @@ *** Changes since GDB 6.4 +* New targets + +Renesas M32C/M16C m32c-elf + +Morpho Technologies ms1 ms1-elf + * New commands init-if-undefined Initialize a convenience variable, but diff --git a/gdb/config/m32c/m32c.mt b/gdb/config/m32c/m32c.mt new file mode 100644 index 0000000000..2a404d45b6 --- /dev/null +++ b/gdb/config/m32c/m32c.mt @@ -0,0 +1,7 @@ +# Target: Renesas M32C family +TDEPFILES = m32c-tdep.o prologue-value.o + +# There may also be a SID / CGEN simulator for this, but we do have DJ +# Delorie's mini-sim. +SIM_OBS = remote-sim.o +SIM = ../sim/m32c/libsim.a diff --git a/gdb/configure.tgt b/gdb/configure.tgt index 4092fe12d9..f6e1ad899f 100644 --- a/gdb/configure.tgt +++ b/gdb/configure.tgt @@ -107,6 +107,8 @@ ia64*-*-*) gdb_target=ia64 ;; iq2000-*-*) gdb_target=iq2000 ;; +m32c-*-*) gdb_target=m32c ;; + m32r*-*-linux*) gdb_target=linux ;; m32r*-*-*) gdb_target=m32r ;; diff --git a/gdb/m32c-tdep.c b/gdb/m32c-tdep.c new file mode 100644 index 0000000000..e93a98cdae --- /dev/null +++ b/gdb/m32c-tdep.c @@ -0,0 +1,2552 @@ +/* Renesas M32C target-dependent code for GDB, the GNU debugger. + + Copyright 2004, 2005 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include "defs.h" + +#include + +#if defined (HAVE_STRING_H) +#include +#endif + +#include "gdb_assert.h" +#include "elf-bfd.h" +#include "elf/m32c.h" +#include "gdb/sim-m32c.h" +#include "dis-asm.h" +#include "gdbtypes.h" +#include "regcache.h" +#include "arch-utils.h" +#include "frame.h" +#include "frame-unwind.h" +#include "dwarf2-frame.h" +#include "dwarf2expr.h" +#include "symtab.h" +#include "gdbcore.h" +#include "value.h" +#include "reggroups.h" +#include "prologue-value.h" +#include "target.h" + + +/* The m32c tdep structure. */ + +static struct reggroup *m32c_dma_reggroup; + +struct m32c_reg; + +/* The type of a function that moves the value of REG between CACHE or + BUF --- in either direction. */ +typedef void (m32c_move_reg_t) (struct m32c_reg *reg, + struct regcache *cache, + void *buf); + +struct m32c_reg +{ + /* The name of this register. */ + const char *name; + + /* Its type. */ + struct type *type; + + /* The architecture this register belongs to. */ + struct gdbarch *arch; + + /* Its GDB register number. */ + int num; + + /* Its sim register number. */ + int sim_num; + + /* Its DWARF register number, or -1 if it doesn't have one. */ + int dwarf_num; + + /* Register group memberships. */ + unsigned int general_p : 1; + unsigned int dma_p : 1; + unsigned int system_p : 1; + unsigned int save_restore_p : 1; + + /* Functions to read its value from a regcache, and write its value + to a regcache. */ + m32c_move_reg_t *read, *write; + + /* Data for READ and WRITE functions. The exact meaning depends on + the specific functions selected; see the comments for those + functions. */ + struct m32c_reg *rx, *ry; + int n; +}; + + +/* An overestimate of the number of raw and pseudoregisters we will + have. The exact answer depends on the variant of the architecture + at hand, but we can use this to declare statically allocated + arrays, and bump it up when needed. */ +#define M32C_MAX_NUM_REGS (75) + +/* The largest assigned DWARF register number. */ +#define M32C_MAX_DWARF_REGNUM (40) + + +struct gdbarch_tdep +{ + /* All the registers for this variant, indexed by GDB register + number, and the number of registers present. */ + struct m32c_reg regs[M32C_MAX_NUM_REGS]; + + /* The number of valid registers. */ + int num_regs; + + /* Interesting registers. These are pointers into REGS. */ + struct m32c_reg *pc, *flg; + struct m32c_reg *r0, *r1, *r2, *r3, *a0, *a1; + struct m32c_reg *r2r0, *r3r2r1r0, *r3r1r2r0; + struct m32c_reg *sb, *fb, *sp; + + /* A table indexed by DWARF register numbers, pointing into + REGS. */ + struct m32c_reg *dwarf_regs[M32C_MAX_DWARF_REGNUM + 1]; + + /* Types for this architecture. We can't use the builtin_type_foo + types, because they're not initialized when building a gdbarch + structure. */ + struct type *voyd, *ptr_voyd, *func_voyd; + struct type *uint8, *uint16; + struct type *int8, *int16, *int32, *int64; + + /* The types for data address and code address registers. */ + struct type *data_addr_reg_type, *code_addr_reg_type; + + /* The number of bytes a return address pushed by a 'jsr' instruction + occupies on the stack. */ + int ret_addr_bytes; + + /* The number of bytes an address register occupies on the stack + when saved by an 'enter' or 'pushm' instruction. */ + int push_addr_bytes; +}; + + +/* Types. */ + +static void +make_types (struct gdbarch *arch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + unsigned long mach = gdbarch_bfd_arch_info (arch)->mach; + int data_addr_reg_bits, code_addr_reg_bits; + char type_name[50]; + +#if 0 + /* This is used to clip CORE_ADDR values, so this value is + appropriate both on the m32c, where pointers are 32 bits long, + and on the m16c, where pointers are sixteen bits long, but there + may be code above the 64k boundary. */ + set_gdbarch_addr_bit (arch, 24); +#else + /* GCC uses 32 bits for addrs in the dwarf info, even though + only 16/24 bits are used. Setting addr_bit to 24 causes + errors in reading the dwarf addresses. */ + set_gdbarch_addr_bit (arch, 32); +#endif + + set_gdbarch_int_bit (arch, 16); + switch (mach) + { + case bfd_mach_m16c: + data_addr_reg_bits = 16; + code_addr_reg_bits = 24; + set_gdbarch_ptr_bit (arch, 16); + tdep->ret_addr_bytes = 3; + tdep->push_addr_bytes = 2; + break; + + case bfd_mach_m32c: + data_addr_reg_bits = 24; + code_addr_reg_bits = 24; + set_gdbarch_ptr_bit (arch, 32); + tdep->ret_addr_bytes = 4; + tdep->push_addr_bytes = 4; + break; + + default: + gdb_assert (0); + } + + /* The builtin_type_mumble variables are sometimes uninitialized when + this is called, so we avoid using them. */ + tdep->voyd = init_type (TYPE_CODE_VOID, 1, 0, "void", NULL); + tdep->ptr_voyd = init_type (TYPE_CODE_PTR, gdbarch_ptr_bit (arch) / 8, + TYPE_FLAG_UNSIGNED, NULL, NULL); + TYPE_TARGET_TYPE (tdep->ptr_voyd) = tdep->voyd; + tdep->func_voyd = lookup_function_type (tdep->voyd); + + sprintf (type_name, "%s_data_addr_t", + gdbarch_bfd_arch_info (arch)->printable_name); + tdep->data_addr_reg_type + = init_type (TYPE_CODE_PTR, data_addr_reg_bits / 8, + TYPE_FLAG_UNSIGNED, xstrdup (type_name), NULL); + TYPE_TARGET_TYPE (tdep->data_addr_reg_type) = tdep->voyd; + + sprintf (type_name, "%s_code_addr_t", + gdbarch_bfd_arch_info (arch)->printable_name); + tdep->code_addr_reg_type + = init_type (TYPE_CODE_PTR, code_addr_reg_bits / 8, + TYPE_FLAG_UNSIGNED, xstrdup (type_name), NULL); + TYPE_TARGET_TYPE (tdep->code_addr_reg_type) = tdep->func_voyd; + + tdep->uint8 = init_type (TYPE_CODE_INT, 1, TYPE_FLAG_UNSIGNED, + "uint8_t", NULL); + tdep->uint16 = init_type (TYPE_CODE_INT, 2, TYPE_FLAG_UNSIGNED, + "uint16_t", NULL); + tdep->int8 = init_type (TYPE_CODE_INT, 1, 0, "int8_t", NULL); + tdep->int16 = init_type (TYPE_CODE_INT, 2, 0, "int16_t", NULL); + tdep->int32 = init_type (TYPE_CODE_INT, 4, 0, "int32_t", NULL); + tdep->int64 = init_type (TYPE_CODE_INT, 8, 0, "int64_t", NULL); +} + + + +/* Register set. */ + +static const char * +m32c_register_name (int num) +{ + return gdbarch_tdep (current_gdbarch)->regs[num].name; +} + + +static struct type * +m32c_register_type (struct gdbarch *arch, int reg_nr) +{ + return gdbarch_tdep (arch)->regs[reg_nr].type; +} + + +static int +m32c_register_sim_regno (int reg_nr) +{ + return gdbarch_tdep (current_gdbarch)->regs[reg_nr].sim_num; +} + + +static int +m32c_debug_info_reg_to_regnum (int reg_nr) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + if (0 <= reg_nr && reg_nr <= M32C_MAX_DWARF_REGNUM + && tdep->dwarf_regs[reg_nr]) + return tdep->dwarf_regs[reg_nr]->num; + else + /* The DWARF CFI code expects to see -1 for invalid register + numbers. */ + return -1; +} + + +int +m32c_register_reggroup_p (struct gdbarch *gdbarch, int regnum, + struct reggroup *group) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + struct m32c_reg *reg = &tdep->regs[regnum]; + + /* The anonymous raw registers aren't in any groups. */ + if (! reg->name) + return 0; + + if (group == all_reggroup) + return 1; + + if (group == general_reggroup + && reg->general_p) + return 1; + + if (group == m32c_dma_reggroup + && reg->dma_p) + return 1; + + if (group == system_reggroup + && reg->system_p) + return 1; + + /* Since the m32c DWARF register numbers refer to cooked registers, not + raw registers, and frame_pop depends on the save and restore groups + containing registers the DWARF CFI will actually mention, our save + and restore groups are cooked registers, not raw registers. (This is + why we can't use the default reggroup function.) */ + if ((group == save_reggroup + || group == restore_reggroup) + && reg->save_restore_p) + return 1; + + return 0; +} + + +/* Register move functions. We declare them here using + m32c_move_reg_t to check the types. */ +static m32c_move_reg_t m32c_raw_read, m32c_raw_write; +static m32c_move_reg_t m32c_banked_read, m32c_banked_write; +static m32c_move_reg_t m32c_sb_read, m32c_sb_write; +static m32c_move_reg_t m32c_part_read, m32c_part_write; +static m32c_move_reg_t m32c_cat_read, m32c_cat_write; +static m32c_move_reg_t m32c_r3r2r1r0_read, m32c_r3r2r1r0_write; + + +/* Copy the value of the raw register REG from CACHE to BUF. */ +static void +m32c_raw_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + regcache_raw_read (cache, reg->num, buf); +} + + +/* Copy the value of the raw register REG from BUF to CACHE. */ +static void +m32c_raw_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + regcache_raw_write (cache, reg->num, (const void *) buf); +} + + +/* Return the value of the 'flg' register in CACHE. */ +static int +m32c_read_flg (struct regcache *cache) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (cache)); + ULONGEST flg; + regcache_raw_read_unsigned (cache, tdep->flg->num, &flg); + return flg & 0xffff; +} + + +/* Move the value of a banked register from CACHE to BUF. + If the value of the 'flg' register in CACHE has any of the bits + masked in REG->n set, then read REG->ry. Otherwise, read + REG->rx. */ +static void +m32c_banked_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + struct m32c_reg *bank_reg + = ((m32c_read_flg (cache) & reg->n) ? reg->ry : reg->rx); + regcache_raw_read (cache, bank_reg->num, buf); +} + + +/* Move the value of a banked register from BUF to CACHE. + If the value of the 'flg' register in CACHE has any of the bits + masked in REG->n set, then write REG->ry. Otherwise, write + REG->rx. */ +static void +m32c_banked_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + struct m32c_reg *bank_reg + = ((m32c_read_flg (cache) & reg->n) ? reg->ry : reg->rx); + regcache_raw_write (cache, bank_reg->num, (const void *) buf); +} + + +/* Move the value of SB from CACHE to BUF. On bfd_mach_m32c, SB is a + banked register; on bfd_mach_m16c, it's not. */ +static void +m32c_sb_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + if (gdbarch_bfd_arch_info (reg->arch)->mach == bfd_mach_m16c) + m32c_raw_read (reg->rx, cache, buf); + else + m32c_banked_read (reg, cache, buf); +} + + +/* Move the value of SB from BUF to CACHE. On bfd_mach_m32c, SB is a + banked register; on bfd_mach_m16c, it's not. */ +static void +m32c_sb_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + if (gdbarch_bfd_arch_info (reg->arch)->mach == bfd_mach_m16c) + m32c_raw_write (reg->rx, cache, buf); + else + m32c_banked_write (reg, cache, buf); +} + + +/* Assuming REG uses m32c_part_read and m32c_part_write, set *OFFSET_P + and *LEN_P to the offset and length, in bytes, of the part REG + occupies in its underlying register. The offset is from the + lower-addressed end, regardless of the architecture's endianness. + (The M32C family is always little-endian, but let's keep those + assumptions out of here.) */ +static void +m32c_find_part (struct m32c_reg *reg, int *offset_p, int *len_p) +{ + /* The length of the containing register, of which REG is one part. */ + int containing_len = TYPE_LENGTH (reg->rx->type); + + /* The length of one "element" in our imaginary array. */ + int elt_len = TYPE_LENGTH (reg->type); + + /* The offset of REG's "element" from the least significant end of + the containing register. */ + int elt_offset = reg->n * elt_len; + + /* If we extend off the end, trim the length of the element. */ + if (elt_offset + elt_len > containing_len) + { + elt_len = containing_len - elt_offset; + /* We shouldn't be declaring partial registers that go off the + end of their containing registers. */ + gdb_assert (elt_len > 0); + } + + /* Flip the offset around if we're big-endian. */ + if (gdbarch_byte_order (reg->arch) == BFD_ENDIAN_BIG) + elt_offset = TYPE_LENGTH (reg->rx->type) - elt_offset - elt_len; + + *offset_p = elt_offset; + *len_p = elt_len; +} + + +/* Move the value of a partial register (r0h, intbl, etc.) from CACHE + to BUF. Treating the value of the register REG->rx as an array of + REG->type values, where higher indices refer to more significant + bits, read the value of the REG->n'th element. */ +static void +m32c_part_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + int offset, len; + memset (buf, 0, TYPE_LENGTH (reg->type)); + m32c_find_part (reg, &offset, &len); + regcache_cooked_read_part (cache, reg->rx->num, offset, len, buf); +} + + +/* Move the value of a banked register from BUF to CACHE. + Treating the value of the register REG->rx as an array of REG->type + values, where higher indices refer to more significant bits, write + the value of the REG->n'th element. */ +static void +m32c_part_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + int offset, len; + m32c_find_part (reg, &offset, &len); + regcache_cooked_write_part (cache, reg->rx->num, offset, len, buf); +} + + +/* Move the value of REG from CACHE to BUF. REG's value is the + concatenation of the values of the registers REG->rx and REG->ry, + with REG->rx contributing the more significant bits. */ +static void +m32c_cat_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + int high_bytes = TYPE_LENGTH (reg->rx->type); + int low_bytes = TYPE_LENGTH (reg->ry->type); + /* For address arithmetic. */ + unsigned char *cbuf = buf; + + gdb_assert (TYPE_LENGTH (reg->type) == high_bytes + low_bytes); + + if (gdbarch_byte_order (reg->arch) == BFD_ENDIAN_BIG) + { + regcache_cooked_read (cache, reg->rx->num, cbuf); + regcache_cooked_read (cache, reg->ry->num, cbuf + high_bytes); + } + else + { + regcache_cooked_read (cache, reg->rx->num, cbuf + low_bytes); + regcache_cooked_read (cache, reg->ry->num, cbuf); + } +} + + +/* Move the value of REG from CACHE to BUF. REG's value is the + concatenation of the values of the registers REG->rx and REG->ry, + with REG->rx contributing the more significant bits. */ +static void +m32c_cat_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + int high_bytes = TYPE_LENGTH (reg->rx->type); + int low_bytes = TYPE_LENGTH (reg->ry->type); + /* For address arithmetic. */ + unsigned char *cbuf = buf; + + gdb_assert (TYPE_LENGTH (reg->type) == high_bytes + low_bytes); + + if (gdbarch_byte_order (reg->arch) == BFD_ENDIAN_BIG) + { + regcache_cooked_write (cache, reg->rx->num, cbuf); + regcache_cooked_write (cache, reg->ry->num, cbuf + high_bytes); + } + else + { + regcache_cooked_write (cache, reg->rx->num, cbuf + low_bytes); + regcache_cooked_write (cache, reg->ry->num, cbuf); + } +} + + +/* Copy the value of the raw register REG from CACHE to BUF. REG is + the concatenation (from most significant to least) of r3, r2, r1, + and r0. */ +static void +m32c_r3r2r1r0_read (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (reg->arch); + int len = TYPE_LENGTH (tdep->r0->type); + + /* For address arithmetic. */ + unsigned char *cbuf = buf; + + if (gdbarch_byte_order (reg->arch) == BFD_ENDIAN_BIG) + { + regcache_cooked_read (cache, tdep->r0->num, cbuf + len * 3); + regcache_cooked_read (cache, tdep->r1->num, cbuf + len * 2); + regcache_cooked_read (cache, tdep->r2->num, cbuf + len * 1); + regcache_cooked_read (cache, tdep->r3->num, cbuf); + } + else + { + regcache_cooked_read (cache, tdep->r0->num, cbuf); + regcache_cooked_read (cache, tdep->r1->num, cbuf + len * 1); + regcache_cooked_read (cache, tdep->r2->num, cbuf + len * 2); + regcache_cooked_read (cache, tdep->r3->num, cbuf + len * 3); + } +} + + +/* Copy the value of the raw register REG from BUF to CACHE. REG is + the concatenation (from most significant to least) of r3, r2, r1, + and r0. */ +static void +m32c_r3r2r1r0_write (struct m32c_reg *reg, struct regcache *cache, void *buf) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (reg->arch); + int len = TYPE_LENGTH (tdep->r0->type); + + /* For address arithmetic. */ + unsigned char *cbuf = buf; + + if (gdbarch_byte_order (reg->arch) == BFD_ENDIAN_BIG) + { + regcache_cooked_write (cache, tdep->r0->num, cbuf + len * 3); + regcache_cooked_write (cache, tdep->r1->num, cbuf + len * 2); + regcache_cooked_write (cache, tdep->r2->num, cbuf + len * 1); + regcache_cooked_write (cache, tdep->r3->num, cbuf); + } + else + { + regcache_cooked_write (cache, tdep->r0->num, cbuf); + regcache_cooked_write (cache, tdep->r1->num, cbuf + len * 1); + regcache_cooked_write (cache, tdep->r2->num, cbuf + len * 2); + regcache_cooked_write (cache, tdep->r3->num, cbuf + len * 3); + } +} + + +static void +m32c_pseudo_register_read (struct gdbarch *arch, + struct regcache *cache, + int cookednum, + gdb_byte *buf) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + struct m32c_reg *reg; + + gdb_assert (0 <= cookednum && cookednum < tdep->num_regs); + gdb_assert (arch == get_regcache_arch (cache)); + gdb_assert (arch == tdep->regs[cookednum].arch); + reg = &tdep->regs[cookednum]; + + reg->read (reg, cache, buf); +} + + +static void +m32c_pseudo_register_write (struct gdbarch *arch, + struct regcache *cache, + int cookednum, + const gdb_byte *buf) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + struct m32c_reg *reg; + + gdb_assert (0 <= cookednum && cookednum < tdep->num_regs); + gdb_assert (arch == get_regcache_arch (cache)); + gdb_assert (arch == tdep->regs[cookednum].arch); + reg = &tdep->regs[cookednum]; + + reg->write (reg, cache, (void *) buf); +} + + +/* Add a register with the given fields to the end of ARCH's table. + Return a pointer to the newly added register. */ +static struct m32c_reg * +add_reg (struct gdbarch *arch, + const char *name, + struct type *type, + int sim_num, + m32c_move_reg_t *read, + m32c_move_reg_t *write, + struct m32c_reg *rx, + struct m32c_reg *ry, + int n) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + struct m32c_reg *r = &tdep->regs[tdep->num_regs]; + + gdb_assert (tdep->num_regs < M32C_MAX_NUM_REGS); + + r->name = name; + r->type = type; + r->arch = arch; + r->num = tdep->num_regs; + r->sim_num = sim_num; + r->dwarf_num = -1; + r->general_p = 0; + r->dma_p = 0; + r->system_p = 0; + r->save_restore_p = 0; + r->read = read; + r->write = write; + r->rx = rx; + r->ry = ry; + r->n = n; + + tdep->num_regs++; + + return r; +} + + +/* Record NUM as REG's DWARF register number. */ +static void +set_dwarf_regnum (struct m32c_reg *reg, int num) +{ + gdb_assert (num < M32C_MAX_NUM_REGS); + + /* Update the reg->DWARF mapping. Only count the first number + assigned to this register. */ + if (reg->dwarf_num == -1) + reg->dwarf_num = num; + + /* Update the DWARF->reg mapping. */ + gdbarch_tdep (reg->arch)->dwarf_regs[num] = reg; +} + + +/* Mark REG as a general-purpose register, and return it. */ +static struct m32c_reg * +mark_general (struct m32c_reg *reg) +{ + reg->general_p = 1; + return reg; +} + + +/* Mark REG as a DMA register, and return it. */ +static struct m32c_reg * +mark_dma (struct m32c_reg *reg) +{ + reg->dma_p = 1; + return reg; +} + + +/* Mark REG as a SYSTEM register, and return it. */ +static struct m32c_reg * +mark_system (struct m32c_reg *reg) +{ + reg->system_p = 1; + return reg; +} + + +/* Mark REG as a save-restore register, and return it. */ +static struct m32c_reg * +mark_save_restore (struct m32c_reg *reg) +{ + reg->save_restore_p = 1; + return reg; +} + + +#define FLAGBIT_B 0x0010 +#define FLAGBIT_U 0x0080 + +/* Handy macros for declaring registers. These all evaluate to + pointers to the register declared. Macros that define two + registers evaluate to a pointer to the first. */ + +/* A raw register named NAME, with type TYPE and sim number SIM_NUM. */ +#define R(name, type, sim_num) \ + (add_reg (arch, (name), (type), (sim_num), \ + m32c_raw_read, m32c_raw_write, NULL, NULL, 0)) + +/* The simulator register number for a raw register named NAME. */ +#define SIM(name) (m32c_sim_reg_ ## name) + +/* A raw unsigned 16-bit data register named NAME. + NAME should be an identifier, not a string. */ +#define R16U(name) \ + (R(#name, tdep->uint16, SIM (name))) + +/* A raw data address register named NAME. + NAME should be an identifier, not a string. */ +#define RA(name) \ + (R(#name, tdep->data_addr_reg_type, SIM (name))) + +/* A raw code address register named NAME. NAME should + be an identifier, not a string. */ +#define RC(name) \ + (R(#name, tdep->code_addr_reg_type, SIM (name))) + +/* A pair of raw registers named NAME0 and NAME1, with type TYPE. + NAME should be an identifier, not a string. */ +#define RP(name, type) \ + (R(#name "0", (type), SIM (name ## 0)), \ + R(#name "1", (type), SIM (name ## 1)) - 1) + +/* A raw banked general-purpose data register named NAME. + NAME should be an identifier, not a string. */ +#define RBD(name) \ + (R(NULL, tdep->int16, SIM (name ## _bank0)), \ + R(NULL, tdep->int16, SIM (name ## _bank1)) - 1) + +/* A raw banked data address register named NAME. + NAME should be an identifier, not a string. */ +#define RBA(name) \ + (R(NULL, tdep->data_addr_reg_type, SIM (name ## _bank0)), \ + R(NULL, tdep->data_addr_reg_type, SIM (name ## _bank1)) - 1) + +/* A cooked register named NAME referring to a raw banked register + from the bank selected by the current value of FLG. RAW_PAIR + should be a pointer to the first register in the banked pair. + NAME must be an identifier, not a string. */ +#define CB(name, raw_pair) \ + (add_reg (arch, #name, (raw_pair)->type, 0, \ + m32c_banked_read, m32c_banked_write, \ + (raw_pair), (raw_pair + 1), FLAGBIT_B)) + +/* A pair of registers named NAMEH and NAMEL, of type TYPE, that + access the top and bottom halves of the register pointed to by + NAME. NAME should be an identifier. */ +#define CHL(name, type) \ + (add_reg (arch, #name "h", (type), 0, \ + m32c_part_read, m32c_part_write, name, NULL, 1), \ + add_reg (arch, #name "l", (type), 0, \ + m32c_part_read, m32c_part_write, name, NULL, 0) - 1) + +/* A register constructed by concatenating the two registers HIGH and + LOW, whose name is HIGHLOW and whose type is TYPE. */ +#define CCAT(high, low, type) \ + (add_reg (arch, #high #low, (type), 0, \ + m32c_cat_read, m32c_cat_write, (high), (low), 0)) + +/* Abbreviations for marking register group membership. */ +#define G(reg) (mark_general (reg)) +#define S(reg) (mark_system (reg)) +#define DMA(reg) (mark_dma (reg)) + + +/* Construct the register set for ARCH. */ +static void +make_regs (struct gdbarch *arch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + int mach = gdbarch_bfd_arch_info (arch)->mach; + + struct m32c_reg *raw_r0_pair = RBD (r0); + struct m32c_reg *raw_r1_pair = RBD (r1); + struct m32c_reg *raw_r2_pair = RBD (r2); + struct m32c_reg *raw_r3_pair = RBD (r3); + struct m32c_reg *raw_a0_pair = RBA (a0); + struct m32c_reg *raw_a1_pair = RBA (a1); + struct m32c_reg *raw_fb_pair = RBA (fb); + + /* sb is banked on the bfd_mach_m32c, but not on bfd_mach_m16c. + We always declare both raw registers, and deal with the distinction + in the pseudoregister. */ + struct m32c_reg *raw_sb_pair = RBA (sb); + + struct m32c_reg *usp = S (RA (usp)); + struct m32c_reg *isp = S (RA (isp)); + struct m32c_reg *intb = S (RC (intb)); + struct m32c_reg *pc = G (RC (pc)); + struct m32c_reg *flg = G (R16U (flg)); + + if (mach == bfd_mach_m32c) + { + struct m32c_reg *svf = S (R16U (svf)); + struct m32c_reg *svp = S (RC (svp)); + struct m32c_reg *vct = S (RC (vct)); + + struct m32c_reg *dmd01 = DMA (RP (dmd, tdep->uint8)); + struct m32c_reg *dct01 = DMA (RP (dct, tdep->uint16)); + struct m32c_reg *drc01 = DMA (RP (drc, tdep->uint16)); + struct m32c_reg *dma01 = DMA (RP (dma, tdep->data_addr_reg_type)); + struct m32c_reg *dsa01 = DMA (RP (dsa, tdep->data_addr_reg_type)); + struct m32c_reg *dra01 = DMA (RP (dra, tdep->data_addr_reg_type)); + } + + int num_raw_regs = tdep->num_regs; + + struct m32c_reg *r0 = G (CB (r0, raw_r0_pair)); + struct m32c_reg *r1 = G (CB (r1, raw_r1_pair)); + struct m32c_reg *r2 = G (CB (r2, raw_r2_pair)); + struct m32c_reg *r3 = G (CB (r3, raw_r3_pair)); + struct m32c_reg *a0 = G (CB (a0, raw_a0_pair)); + struct m32c_reg *a1 = G (CB (a1, raw_a1_pair)); + struct m32c_reg *fb = G (CB (fb, raw_fb_pair)); + + /* sb is banked on the bfd_mach_m32c, but not on bfd_mach_m16c. + Specify custom read/write functions that do the right thing. */ + struct m32c_reg *sb + = G (add_reg (arch, "sb", raw_sb_pair->type, 0, + m32c_sb_read, m32c_sb_write, + raw_sb_pair, raw_sb_pair + 1, 0)); + + /* The current sp is either usp or isp, depending on the value of + the FLG register's U bit. */ + struct m32c_reg *sp + = G (add_reg (arch, "sp", usp->type, 0, + m32c_banked_read, m32c_banked_write, isp, usp, FLAGBIT_U)); + + struct m32c_reg *r0hl = CHL (r0, tdep->int8); + struct m32c_reg *r1hl = CHL (r1, tdep->int8); + struct m32c_reg *r2hl = CHL (r2, tdep->int8); + struct m32c_reg *r3hl = CHL (r3, tdep->int8); + struct m32c_reg *intbhl = CHL (intb, tdep->int16); + + struct m32c_reg *r2r0 = CCAT (r2, r0, tdep->int32); + struct m32c_reg *r3r1 = CCAT (r3, r1, tdep->int32); + struct m32c_reg *r3r1r2r0 = CCAT (r3r1, r2r0, tdep->int64); + + struct m32c_reg *r3r2r1r0 + = add_reg (arch, "r3r2r1r0", tdep->int64, 0, + m32c_r3r2r1r0_read, m32c_r3r2r1r0_write, NULL, NULL, 0); + + struct m32c_reg *a1a0; + if (mach == bfd_mach_m16c) + a1a0 = CCAT (a1, a0, tdep->int32); + else + a1a0 = NULL; + + int num_cooked_regs = tdep->num_regs - num_raw_regs; + + tdep->pc = pc; + tdep->flg = flg; + tdep->r0 = r0; + tdep->r1 = r1; + tdep->r2 = r2; + tdep->r3 = r3; + tdep->r2r0 = r2r0; + tdep->r3r2r1r0 = r3r2r1r0; + tdep->r3r1r2r0 = r3r1r2r0; + tdep->a0 = a0; + tdep->a1 = a1; + tdep->sb = sb; + tdep->fb = fb; + tdep->sp = sp; + + /* Set up the DWARF register table. */ + memset (tdep->dwarf_regs, 0, sizeof (tdep->dwarf_regs)); + set_dwarf_regnum (r0hl + 1, 0x01); + set_dwarf_regnum (r0hl + 0, 0x02); + set_dwarf_regnum (r1hl + 1, 0x03); + set_dwarf_regnum (r1hl + 0, 0x04); + set_dwarf_regnum (r0, 0x05); + set_dwarf_regnum (r1, 0x06); + set_dwarf_regnum (r2, 0x07); + set_dwarf_regnum (r3, 0x08); + set_dwarf_regnum (a0, 0x09); + set_dwarf_regnum (a1, 0x0a); + set_dwarf_regnum (fb, 0x0b); + set_dwarf_regnum (sp, 0x0c); + set_dwarf_regnum (pc, 0x0d); /* GCC's invention */ + set_dwarf_regnum (sb, 0x13); + set_dwarf_regnum (r2r0, 0x15); + set_dwarf_regnum (r3r1, 0x16); + if (a1a0) + set_dwarf_regnum (a1a0, 0x17); + + /* Enumerate the save/restore register group. + + The regcache_save and regcache_restore functions apply their read + function to each register in this group. + + Since frame_pop supplies frame_unwind_register as its read + function, the registers meaningful to the Dwarf unwinder need to + be in this group. + + On the other hand, when we make inferior calls, save_inferior_status + and restore_inferior_status use them to preserve the current register + values across the inferior call. For this, you'd kind of like to + preserve all the raw registers, to protect the interrupted code from + any sort of bank switching the callee might have done. But we handle + those cases so badly anyway --- for example, it matters whether we + restore FLG before or after we restore the general-purpose registers, + but there's no way to express that --- that it isn't worth worrying + about. + + We omit control registers like inthl: if you call a function that + changes those, it's probably because you wanted that change to be + visible to the interrupted code. */ + mark_save_restore (r0); + mark_save_restore (r1); + mark_save_restore (r2); + mark_save_restore (r3); + mark_save_restore (a0); + mark_save_restore (a1); + mark_save_restore (sb); + mark_save_restore (fb); + mark_save_restore (sp); + mark_save_restore (pc); + mark_save_restore (flg); + + set_gdbarch_num_regs (arch, num_raw_regs); + set_gdbarch_num_pseudo_regs (arch, num_cooked_regs); + set_gdbarch_pc_regnum (arch, pc->num); + set_gdbarch_sp_regnum (arch, sp->num); + set_gdbarch_register_name (arch, m32c_register_name); + set_gdbarch_register_type (arch, m32c_register_type); + set_gdbarch_pseudo_register_read (arch, m32c_pseudo_register_read); + set_gdbarch_pseudo_register_write (arch, m32c_pseudo_register_write); + set_gdbarch_register_sim_regno (arch, m32c_register_sim_regno); + set_gdbarch_stab_reg_to_regnum (arch, m32c_debug_info_reg_to_regnum); + set_gdbarch_dwarf_reg_to_regnum (arch, m32c_debug_info_reg_to_regnum); + set_gdbarch_dwarf2_reg_to_regnum (arch, m32c_debug_info_reg_to_regnum); + set_gdbarch_register_reggroup_p (arch, m32c_register_reggroup_p); + + reggroup_add (arch, general_reggroup); + reggroup_add (arch, all_reggroup); + reggroup_add (arch, save_reggroup); + reggroup_add (arch, restore_reggroup); + reggroup_add (arch, system_reggroup); + reggroup_add (arch, m32c_dma_reggroup); +} + + + +/* Breakpoints. */ + +static const unsigned char * +m32c_breakpoint_from_pc (CORE_ADDR *pc, int *len) +{ + static unsigned char break_insn[] = { 0x00 }; /* brk */ + + *len = sizeof (break_insn); + return break_insn; +} + + + +/* Prologue analysis. */ + +struct m32c_prologue +{ + /* For consistency with the DWARF 2 .debug_frame info generated by + GCC, a frame's CFA is the address immediately after the saved + return address. */ + + /* The architecture for which we generated this prologue info. */ + struct gdbarch *arch; + + enum { + /* This function uses a frame pointer. */ + prologue_with_frame_ptr, + + /* This function has no frame pointer. */ + prologue_sans_frame_ptr, + + /* This function sets up the stack, so its frame is the first + frame on the stack. */ + prologue_first_frame + + } kind; + + /* If KIND is prologue_with_frame_ptr, this is the offset from the + CFA to where the frame pointer points. This is always zero or + negative. */ + LONGEST frame_ptr_offset; + + /* If KIND is prologue_sans_frame_ptr, the offset from the CFA to + the stack pointer --- always zero or negative. + + Calling this a "size" is a bit misleading, but given that the + stack grows downwards, using offsets for everything keeps one + from going completely sign-crazy: you never change anything's + sign for an ADD instruction; always change the second operand's + sign for a SUB instruction; and everything takes care of + itself. + + Functions that use alloca don't have a constant frame size. But + they always have frame pointers, so we must use that to find the + CFA (and perhaps to unwind the stack pointer). */ + LONGEST frame_size; + + /* The address of the first instruction at which the frame has been + set up and the arguments are where the debug info says they are + --- as best as we can tell. */ + CORE_ADDR prologue_end; + + /* reg_offset[R] is the offset from the CFA at which register R is + saved, or 1 if register R has not been saved. (Real values are + always zero or negative.) */ + LONGEST reg_offset[M32C_MAX_NUM_REGS]; +}; + + +/* The longest I've seen, anyway. */ +#define M32C_MAX_INSN_LEN (9) + +/* Processor state, for the prologue analyzer. */ +struct m32c_pv_state +{ + struct gdbarch *arch; + pv_t r0, r1, r2, r3; + pv_t a0, a1; + pv_t sb, fb, sp; + pv_t pc; + struct pv_area *stack; + + /* Bytes from the current PC, the address they were read from, + and the address of the next unconsumed byte. */ + gdb_byte insn[M32C_MAX_INSN_LEN]; + CORE_ADDR scan_pc, next_addr; +}; + + +/* Push VALUE on STATE's stack, occupying SIZE bytes. Return zero if + all went well, or non-zero if simulating the action would trash our + state. */ +static int +m32c_pv_push (struct m32c_pv_state *state, pv_t value, int size) +{ + if (pv_area_store_would_trash (state->stack, state->sp)) + return 1; + + state->sp = pv_add_constant (state->sp, -size); + pv_area_store (state->stack, state->sp, size, value); + + return 0; +} + + +/* A source or destination location for an m16c or m32c + instruction. */ +struct srcdest +{ + /* If srcdest_reg, the location is a register pointed to by REG. + If srcdest_partial_reg, the location is part of a register pointed + to by REG. We don't try to handle this too well. + If srcdest_mem, the location is memory whose address is ADDR. */ + enum { srcdest_reg, srcdest_partial_reg, srcdest_mem } kind; + pv_t *reg, addr; +}; + + +/* Return the SIZE-byte value at LOC in STATE. */ +static pv_t +m32c_srcdest_fetch (struct m32c_pv_state *state, struct srcdest loc, int size) +{ + if (loc.kind == srcdest_mem) + return pv_area_fetch (state->stack, loc.addr, size); + else if (loc.kind == srcdest_partial_reg) + return pv_unknown (); + else + return *loc.reg; +} + + +/* Write VALUE, a SIZE-byte value, to LOC in STATE. Return zero if + all went well, or non-zero if simulating the store would trash our + state. */ +static int +m32c_srcdest_store (struct m32c_pv_state *state, struct srcdest loc, + pv_t value, int size) +{ + if (loc.kind == srcdest_mem) + { + if (pv_area_store_would_trash (state->stack, loc.addr)) + return 1; + pv_area_store (state->stack, loc.addr, size, value); + } + else if (loc.kind == srcdest_partial_reg) + *loc.reg = pv_unknown (); + else + *loc.reg = value; + + return 0; +} + + +static int +m32c_sign_ext (int v, int bits) +{ + int mask = 1 << (bits - 1); + return (v ^ mask) - mask; +} + +static unsigned int +m32c_next_byte (struct m32c_pv_state *st) +{ + gdb_assert (st->next_addr - st->scan_pc < sizeof (st->insn)); + return st->insn[st->next_addr++ - st->scan_pc]; +} + +static int +m32c_udisp8 (struct m32c_pv_state *st) +{ + return m32c_next_byte (st); +} + + +static int +m32c_sdisp8 (struct m32c_pv_state *st) +{ + return m32c_sign_ext (m32c_next_byte (st), 8); +} + + +static int +m32c_udisp16 (struct m32c_pv_state *st) +{ + int low = m32c_next_byte (st); + int high = m32c_next_byte (st); + + return low + (high << 8); +} + + +static int +m32c_sdisp16 (struct m32c_pv_state *st) +{ + int low = m32c_next_byte (st); + int high = m32c_next_byte (st); + + return m32c_sign_ext (low + (high << 8), 16); +} + + +static int +m32c_udisp24 (struct m32c_pv_state *st) +{ + int low = m32c_next_byte (st); + int mid = m32c_next_byte (st); + int high = m32c_next_byte (st); + + return low + (mid << 8) + (high << 16); +} + + +/* Extract the 'source' field from an m32c MOV.size:G-format instruction. */ +static int +m32c_get_src23 (unsigned char *i) +{ + return (((i[0] & 0x70) >> 2) + | ((i[1] & 0x30) >> 4)); +} + + +/* Extract the 'dest' field from an m32c MOV.size:G-format instruction. */ +static int +m32c_get_dest23 (unsigned char *i) +{ + return (((i[0] & 0x0e) << 1) + | ((i[1] & 0xc0) >> 6)); +} + + +static struct srcdest +m32c_decode_srcdest4 (struct m32c_pv_state *st, + int code, int size) +{ + struct srcdest sd; + + if (code < 6) + sd.kind = (size == 2 ? srcdest_reg : srcdest_partial_reg); + else + sd.kind = srcdest_mem; + + switch (code) + { + case 0x0: sd.reg = (size == 1 ? &st->r0 : &st->r0); break; + case 0x1: sd.reg = (size == 1 ? &st->r0 : &st->r1); break; + case 0x2: sd.reg = (size == 1 ? &st->r1 : &st->r2); break; + case 0x3: sd.reg = (size == 1 ? &st->r1 : &st->r3); break; + + case 0x4: sd.reg = &st->a0; break; + case 0x5: sd.reg = &st->a1; break; + + case 0x6: sd.addr = st->a0; break; + case 0x7: sd.addr = st->a1; break; + + case 0x8: sd.addr = pv_add_constant (st->a0, m32c_udisp8 (st)); break; + case 0x9: sd.addr = pv_add_constant (st->a1, m32c_udisp8 (st)); break; + case 0xa: sd.addr = pv_add_constant (st->sb, m32c_udisp8 (st)); break; + case 0xb: sd.addr = pv_add_constant (st->fb, m32c_sdisp8 (st)); break; + + case 0xc: sd.addr = pv_add_constant (st->a0, m32c_udisp16 (st)); break; + case 0xd: sd.addr = pv_add_constant (st->a1, m32c_udisp16 (st)); break; + case 0xe: sd.addr = pv_add_constant (st->sb, m32c_udisp16 (st)); break; + case 0xf: sd.addr = pv_constant (m32c_udisp16 (st)); break; + + default: + gdb_assert (0); + } + + return sd; +} + + +static struct srcdest +m32c_decode_sd23 (struct m32c_pv_state *st, int code, int size, int ind) +{ + struct srcdest sd; + + switch (code) + { + case 0x12: + case 0x13: + case 0x10: + case 0x11: + sd.kind = (size == 1) ? srcdest_partial_reg : srcdest_reg; + break; + + case 0x02: + case 0x03: + sd.kind = (size == 4) ? srcdest_reg : srcdest_partial_reg; + break; + + default: + sd.kind = srcdest_mem; + break; + + } + + switch (code) + { + case 0x12: sd.reg = &st->r0; break; + case 0x13: sd.reg = &st->r1; break; + case 0x10: sd.reg = ((size == 1) ? &st->r0 : &st->r2); break; + case 0x11: sd.reg = ((size == 1) ? &st->r1 : &st->r3); break; + case 0x02: sd.reg = &st->a0; break; + case 0x03: sd.reg = &st->a1; break; + + case 0x00: sd.addr = st->a0; break; + case 0x01: sd.addr = st->a1; break; + case 0x04: sd.addr = pv_add_constant (st->a0, m32c_udisp8 (st)); break; + case 0x05: sd.addr = pv_add_constant (st->a1, m32c_udisp8 (st)); break; + case 0x06: sd.addr = pv_add_constant (st->sb, m32c_udisp8 (st)); break; + case 0x07: sd.addr = pv_add_constant (st->fb, m32c_sdisp8 (st)); break; + case 0x08: sd.addr = pv_add_constant (st->a0, m32c_udisp16 (st)); break; + case 0x09: sd.addr = pv_add_constant (st->a1, m32c_udisp16 (st)); break; + case 0x0a: sd.addr = pv_add_constant (st->sb, m32c_udisp16 (st)); break; + case 0x0b: sd.addr = pv_add_constant (st->fb, m32c_sdisp16 (st)); break; + case 0x0c: sd.addr = pv_add_constant (st->a0, m32c_udisp24 (st)); break; + case 0x0d: sd.addr = pv_add_constant (st->a1, m32c_udisp24 (st)); break; + case 0x0f: sd.addr = pv_constant (m32c_udisp16 (st)); break; + case 0x0e: sd.addr = pv_constant (m32c_udisp24 (st)); break; + default: + gdb_assert (0); + } + + if (ind) + { + sd.addr = m32c_srcdest_fetch (st, sd, 4); + sd.kind = srcdest_mem; + } + + return sd; +} + + +/* The r16c and r32c machines have instructions with similar + semantics, but completely different machine language encodings. So + we break out the semantics into their own functions, and leave + machine-specific decoding in m32c_analyze_prologue. + + The following functions all expect their arguments already decoded, + and they all return zero if analysis should continue past this + instruction, or non-zero if analysis should stop. */ + + +/* Simulate an 'enter SIZE' instruction in STATE. */ +static int +m32c_pv_enter (struct m32c_pv_state *state, int size) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (state->arch); + + /* If simulating this store would require us to forget + everything we know about the stack frame in the name of + accuracy, it would be better to just quit now. */ + if (pv_area_store_would_trash (state->stack, state->sp)) + return 1; + + if (m32c_pv_push (state, state->fb, tdep->push_addr_bytes)) + return 1; + state->fb = state->sp; + state->sp = pv_add_constant (state->sp, -size); + + return 0; +} + + +static int +m32c_pv_pushm_one (struct m32c_pv_state *state, pv_t reg, + int bit, int src, int size) +{ + if (bit & src) + { + if (m32c_pv_push (state, reg, size)) + return 1; + } + + return 0; +} + + +/* Simulate a 'pushm SRC' instruction in STATE. */ +static int +m32c_pv_pushm (struct m32c_pv_state *state, int src) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (state->arch); + + /* The bits in SRC indicating which registers to save are: + r0 r1 r2 r3 a0 a1 sb fb */ + return + ( m32c_pv_pushm_one (state, state->fb, 0x01, src, tdep->push_addr_bytes) + || m32c_pv_pushm_one (state, state->sb, 0x02, src, tdep->push_addr_bytes) + || m32c_pv_pushm_one (state, state->a1, 0x04, src, tdep->push_addr_bytes) + || m32c_pv_pushm_one (state, state->a0, 0x08, src, tdep->push_addr_bytes) + || m32c_pv_pushm_one (state, state->r3, 0x10, src, 2) + || m32c_pv_pushm_one (state, state->r2, 0x20, src, 2) + || m32c_pv_pushm_one (state, state->r1, 0x40, src, 2) + || m32c_pv_pushm_one (state, state->r0, 0x80, src, 2)); +} + +/* Return non-zero if VALUE is the first incoming argument register. */ + +static int +m32c_is_1st_arg_reg (struct m32c_pv_state *state, pv_t value) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (state->arch); + return (value.kind == pvk_register + && (gdbarch_bfd_arch_info (state->arch)->mach == bfd_mach_m16c + ? (value.reg == tdep->r1->num) + : (value.reg == tdep->r0->num)) + && value.k == 0); +} + +/* Return non-zero if VALUE is an incoming argument register. */ + +static int +m32c_is_arg_reg (struct m32c_pv_state *state, pv_t value) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (state->arch); + return (value.kind == pvk_register + && (gdbarch_bfd_arch_info (state->arch)->mach == bfd_mach_m16c + ? (value.reg == tdep->r1->num || value.reg == tdep->r2->num) + : (value.reg == tdep->r0->num)) + && value.k == 0); +} + +/* Return non-zero if a store of VALUE to LOC is probably spilling an + argument register to its stack slot in STATE. Such instructions + should be included in the prologue, if possible. + + The store is a spill if: + - the value being stored is the original value of an argument register; + - the value has not already been stored somewhere in STACK; and + - LOC is a stack slot (e.g., a memory location whose address is + relative to the original value of the SP). */ + +static int +m32c_is_arg_spill (struct m32c_pv_state *st, + struct srcdest loc, + pv_t value) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (st->arch); + + return (m32c_is_arg_reg (st, value) + && loc.kind == srcdest_mem + && pv_is_register (loc.addr, tdep->sp->num) + && ! pv_area_find_reg (st->stack, st->arch, value.reg, 0)); +} + +/* Return non-zero if a store of VALUE to LOC is probably + copying the struct return address into an address register + for immediate use. This is basically a "spill" into the + address register, instead of onto the stack. + + The prerequisites are: + - value being stored is original value of the FIRST arg register; + - value has not already been stored on stack; and + - LOC is an address register (a0 or a1). */ + +static int +m32c_is_struct_return (struct m32c_pv_state *st, + struct srcdest loc, + pv_t value) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (st->arch); + + return (m32c_is_1st_arg_reg (st, value) + && !pv_area_find_reg (st->stack, st->arch, value.reg, 0) + && loc.kind == srcdest_reg + && (pv_is_register (*loc.reg, tdep->a0->num) + || pv_is_register (*loc.reg, tdep->a1->num))); +} + +/* Return non-zero if a 'pushm' saving the registers indicated by SRC + was a register save: + - all the named registers should have their original values, and + - the stack pointer should be at a constant offset from the + original stack pointer. */ +static int +m32c_pushm_is_reg_save (struct m32c_pv_state *st, int src) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (st->arch); + /* The bits in SRC indicating which registers to save are: + r0 r1 r2 r3 a0 a1 sb fb */ + return + (pv_is_register (st->sp, tdep->sp->num) + && (! (src & 0x01) || pv_is_register_k (st->fb, tdep->fb->num, 0)) + && (! (src & 0x02) || pv_is_register_k (st->sb, tdep->sb->num, 0)) + && (! (src & 0x04) || pv_is_register_k (st->a1, tdep->a1->num, 0)) + && (! (src & 0x08) || pv_is_register_k (st->a0, tdep->a0->num, 0)) + && (! (src & 0x10) || pv_is_register_k (st->r3, tdep->r3->num, 0)) + && (! (src & 0x20) || pv_is_register_k (st->r2, tdep->r2->num, 0)) + && (! (src & 0x40) || pv_is_register_k (st->r1, tdep->r1->num, 0)) + && (! (src & 0x80) || pv_is_register_k (st->r0, tdep->r0->num, 0))); +} + + +/* Function for finding saved registers in a 'struct pv_area'; we pass + this to pv_area_scan. + + If VALUE is a saved register, ADDR says it was saved at a constant + offset from the frame base, and SIZE indicates that the whole + register was saved, record its offset in RESULT_UNTYPED. */ +static void +check_for_saved (void *prologue_untyped, pv_t addr, CORE_ADDR size, pv_t value) +{ + struct m32c_prologue *prologue = (struct m32c_prologue *) prologue_untyped; + struct gdbarch *arch = prologue->arch; + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + + /* Is this the unchanged value of some register being saved on the + stack? */ + if (value.kind == pvk_register + && value.k == 0 + && pv_is_register (addr, tdep->sp->num)) + { + /* Some registers require special handling: they're saved as a + larger value than the register itself. */ + CORE_ADDR saved_size = register_size (arch, value.reg); + + if (value.reg == tdep->pc->num) + saved_size = tdep->ret_addr_bytes; + else if (gdbarch_register_type (arch, value.reg) + == tdep->data_addr_reg_type) + saved_size = tdep->push_addr_bytes; + + if (size == saved_size) + { + /* Find which end of the saved value corresponds to our + register. */ + if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG) + prologue->reg_offset[value.reg] + = (addr.k + saved_size - register_size (arch, value.reg)); + else + prologue->reg_offset[value.reg] = addr.k; + } + } +} + + +/* Analyze the function prologue for ARCH at START, going no further + than LIMIT, and place a description of what we found in + PROLOGUE. */ +void +m32c_analyze_prologue (struct gdbarch *arch, + CORE_ADDR start, CORE_ADDR limit, + struct m32c_prologue *prologue) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + unsigned long mach = gdbarch_bfd_arch_info (arch)->mach; + CORE_ADDR after_last_frame_related_insn; + struct cleanup *back_to; + struct m32c_pv_state st; + + st.arch = arch; + st.r0 = pv_register (tdep->r0->num, 0); + st.r1 = pv_register (tdep->r1->num, 0); + st.r2 = pv_register (tdep->r2->num, 0); + st.r3 = pv_register (tdep->r3->num, 0); + st.a0 = pv_register (tdep->a0->num, 0); + st.a1 = pv_register (tdep->a1->num, 0); + st.sb = pv_register (tdep->sb->num, 0); + st.fb = pv_register (tdep->fb->num, 0); + st.sp = pv_register (tdep->sp->num, 0); + st.pc = pv_register (tdep->pc->num, 0); + st.stack = make_pv_area (tdep->sp->num); + back_to = make_cleanup_free_pv_area (st.stack); + + /* Record that the call instruction has saved the return address on + the stack. */ + m32c_pv_push (&st, st.pc, tdep->ret_addr_bytes); + + memset (prologue, 0, sizeof (*prologue)); + prologue->arch = arch; + { + int i; + for (i = 0; i < M32C_MAX_NUM_REGS; i++) + prologue->reg_offset[i] = 1; + } + + st.scan_pc = after_last_frame_related_insn = start; + + while (st.scan_pc < limit) + { + pv_t pre_insn_fb = st.fb; + pv_t pre_insn_sp = st.sp; + + /* In theory we could get in trouble by trying to read ahead + here, when we only know we're expecting one byte. In + practice I doubt anyone will care, and it makes the rest of + the code easier. */ + if (target_read_memory (st.scan_pc, st.insn, sizeof (st.insn))) + /* If we can't fetch the instruction from memory, stop here + and hope for the best. */ + break; + st.next_addr = st.scan_pc; + + /* The assembly instructions are written as they appear in the + section of the processor manuals that describe the + instruction encodings. + + When a single assembly language instruction has several + different machine-language encodings, the manual + distinguishes them by a number in parens, before the + mnemonic. Those numbers are included, as well. + + The srcdest decoding instructions have the same names as the + analogous functions in the simulator. */ + if (mach == bfd_mach_m16c) + { + /* (1) ENTER #imm8 */ + if (st.insn[0] == 0x7c && st.insn[1] == 0xf2) + { + if (m32c_pv_enter (&st, st.insn[2])) + break; + st.next_addr += 3; + } + /* (1) PUSHM src */ + else if (st.insn[0] == 0xec) + { + int src = st.insn[1]; + if (m32c_pv_pushm (&st, src)) + break; + st.next_addr += 2; + + if (m32c_pushm_is_reg_save (&st, src)) + after_last_frame_related_insn = st.next_addr; + } + + /* (6) MOV.size:G src, dest */ + else if ((st.insn[0] & 0xfe) == 0x72) + { + int size = (st.insn[0] & 0x01) ? 2 : 1; + + st.next_addr += 2; + + struct srcdest src + = m32c_decode_srcdest4 (&st, (st.insn[1] >> 4) & 0xf, size); + struct srcdest dest + = m32c_decode_srcdest4 (&st, st.insn[1] & 0xf, size); + pv_t src_value = m32c_srcdest_fetch (&st, src, size); + + if (m32c_is_arg_spill (&st, dest, src_value)) + after_last_frame_related_insn = st.next_addr; + else if (m32c_is_struct_return (&st, dest, src_value)) + after_last_frame_related_insn = st.next_addr; + + if (m32c_srcdest_store (&st, dest, src_value, size)) + break; + } + + /* (1) LDC #IMM16, sp */ + else if (st.insn[0] == 0xeb + && st.insn[1] == 0x50) + { + st.next_addr += 2; + st.sp = pv_constant (m32c_udisp16 (&st)); + } + + else + /* We've hit some instruction we don't know how to simulate. + Strictly speaking, we should set every value we're + tracking to "unknown". But we'll be optimistic, assume + that we have enough information already, and stop + analysis here. */ + break; + } + else + { + int src_indirect = 0; + int dest_indirect = 0; + int i = 0; + + gdb_assert (mach == bfd_mach_m32c); + + /* Check for prefix bytes indicating indirect addressing. */ + if (st.insn[0] == 0x41) + { + src_indirect = 1; + i++; + } + else if (st.insn[0] == 0x09) + { + dest_indirect = 1; + i++; + } + else if (st.insn[0] == 0x49) + { + src_indirect = dest_indirect = 1; + i++; + } + + /* (1) ENTER #imm8 */ + if (st.insn[i] == 0xec) + { + if (m32c_pv_enter (&st, st.insn[i + 1])) + break; + st.next_addr += 2; + } + + /* (1) PUSHM src */ + else if (st.insn[i] == 0x8f) + { + int src = st.insn[i + 1]; + if (m32c_pv_pushm (&st, src)) + break; + st.next_addr += 2; + + if (m32c_pushm_is_reg_save (&st, src)) + after_last_frame_related_insn = st.next_addr; + } + + /* (7) MOV.size:G src, dest */ + else if ((st.insn[i] & 0x80) == 0x80 + && (st.insn[i + 1] & 0x0f) == 0x0b + && m32c_get_src23 (&st.insn[i]) < 20 + && m32c_get_dest23 (&st.insn[i]) < 20) + { + int bw = st.insn[i] & 0x01; + int size = bw ? 2 : 1; + + st.next_addr += 2; + + struct srcdest src + = m32c_decode_sd23 (&st, m32c_get_src23 (&st.insn[i]), + size, src_indirect); + struct srcdest dest + = m32c_decode_sd23 (&st, m32c_get_dest23 (&st.insn[i]), + size, dest_indirect); + pv_t src_value = m32c_srcdest_fetch (&st, src, size); + + if (m32c_is_arg_spill (&st, dest, src_value)) + after_last_frame_related_insn = st.next_addr; + + if (m32c_srcdest_store (&st, dest, src_value, size)) + break; + } + /* (2) LDC #IMM24, sp */ + else if (st.insn[i] == 0xd5 + && st.insn[i + 1] == 0x29) + { + st.next_addr += 2; + st.sp = pv_constant (m32c_udisp24 (&st)); + } + else + /* We've hit some instruction we don't know how to simulate. + Strictly speaking, we should set every value we're + tracking to "unknown". But we'll be optimistic, assume + that we have enough information already, and stop + analysis here. */ + break; + } + + /* If this instruction changed the FB or decreased the SP (i.e., + allocated more stack space), then this may be a good place to + declare the prologue finished. However, there are some + exceptions: + + - If the instruction just changed the FB back to its original + value, then that's probably a restore instruction. The + prologue should definitely end before that. + + - If the instruction increased the value of the SP (that is, + shrunk the frame), then it's probably part of a frame + teardown sequence, and the prologue should end before + that. */ + + if (! pv_is_identical (st.fb, pre_insn_fb)) + { + if (! pv_is_register_k (st.fb, tdep->fb->num, 0)) + after_last_frame_related_insn = st.next_addr; + } + else if (! pv_is_identical (st.sp, pre_insn_sp)) + { + /* The comparison of the constants looks odd, there, because + .k is unsigned. All it really means is that the SP is + lower than it was before the instruction. */ + if ( pv_is_register (pre_insn_sp, tdep->sp->num) + && pv_is_register (st.sp, tdep->sp->num) + && ((pre_insn_sp.k - st.sp.k) < (st.sp.k - pre_insn_sp.k))) + after_last_frame_related_insn = st.next_addr; + } + + st.scan_pc = st.next_addr; + } + + /* Did we load a constant value into the stack pointer? */ + if (pv_is_constant (st.sp)) + prologue->kind = prologue_first_frame; + + /* Alternatively, did we initialize the frame pointer? Remember + that the CFA is the address after the return address. */ + if (pv_is_register (st.fb, tdep->sp->num)) + { + prologue->kind = prologue_with_frame_ptr; + prologue->frame_ptr_offset = st.fb.k; + } + + /* Is the frame size a known constant? Remember that frame_size is + actually the offset from the CFA to the SP (i.e., a negative + value). */ + else if (pv_is_register (st.sp, tdep->sp->num)) + { + prologue->kind = prologue_sans_frame_ptr; + prologue->frame_size = st.sp.k; + } + + /* We haven't been able to make sense of this function's frame. Treat + it as the first frame. */ + else + prologue->kind = prologue_first_frame; + + /* Record where all the registers were saved. */ + pv_area_scan (st.stack, check_for_saved, (void *) prologue); + + prologue->prologue_end = after_last_frame_related_insn; + + do_cleanups (back_to); +} + + +static CORE_ADDR +m32c_skip_prologue (CORE_ADDR ip) +{ + char *name; + CORE_ADDR func_addr, func_end, sal_end; + struct m32c_prologue p; + + /* Try to find the extent of the function that contains IP. */ + if (! find_pc_partial_function (ip, &name, &func_addr, &func_end)) + return ip; + + /* Find end by prologue analysis. */ + m32c_analyze_prologue (current_gdbarch, ip, func_end, &p); + /* Find end by line info. */ + sal_end = skip_prologue_using_sal (ip); + /* Return whichever is lower. */ + if (sal_end != 0 && sal_end != ip && sal_end < p.prologue_end) + return sal_end; + else + return p.prologue_end; +} + + + +/* Stack unwinding. */ + +static struct m32c_prologue * +m32c_analyze_frame_prologue (struct frame_info *next_frame, + void **this_prologue_cache) +{ + if (! *this_prologue_cache) + { + CORE_ADDR func_start = frame_func_unwind (next_frame); + CORE_ADDR stop_addr = frame_pc_unwind (next_frame); + + /* If we couldn't find any function containing the PC, then + just initialize the prologue cache, but don't do anything. */ + if (! func_start) + stop_addr = func_start; + + *this_prologue_cache = FRAME_OBSTACK_ZALLOC (struct m32c_prologue); + m32c_analyze_prologue (get_frame_arch (next_frame), + func_start, stop_addr, *this_prologue_cache); + } + + return *this_prologue_cache; +} + + +static CORE_ADDR +m32c_frame_base (struct frame_info *next_frame, + void **this_prologue_cache) +{ + struct m32c_prologue *p + = m32c_analyze_frame_prologue (next_frame, this_prologue_cache); + struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (next_frame)); + + /* In functions that use alloca, the distance between the stack + pointer and the frame base varies dynamically, so we can't use + the SP plus static information like prologue analysis to find the + frame base. However, such functions must have a frame pointer, + to be able to restore the SP on exit. So whenever we do have a + frame pointer, use that to find the base. */ + switch (p->kind) + { + case prologue_with_frame_ptr: + { + CORE_ADDR fb + = frame_unwind_register_unsigned (next_frame, tdep->fb->num); + return fb - p->frame_ptr_offset; + } + + case prologue_sans_frame_ptr: + { + CORE_ADDR sp + = frame_unwind_register_unsigned (next_frame, tdep->sp->num); + return sp - p->frame_size; + } + + case prologue_first_frame: + return 0; + + default: + gdb_assert (0); + } +} + + +static void +m32c_this_id (struct frame_info *next_frame, + void **this_prologue_cache, + struct frame_id *this_id) +{ + CORE_ADDR base = m32c_frame_base (next_frame, this_prologue_cache); + + if (base) + *this_id = frame_id_build (base, frame_func_unwind (next_frame)); + /* Otherwise, leave it unset, and that will terminate the backtrace. */ +} + + +static void +m32c_prev_register (struct frame_info *next_frame, + void **this_prologue_cache, + int regnum, int *optimizedp, + enum lval_type *lvalp, CORE_ADDR *addrp, + int *realnump, gdb_byte *bufferp) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (next_frame)); + struct m32c_prologue *p + = m32c_analyze_frame_prologue (next_frame, this_prologue_cache); + CORE_ADDR frame_base = m32c_frame_base (next_frame, this_prologue_cache); + int reg_size = register_size (get_frame_arch (next_frame), regnum); + + if (regnum == tdep->sp->num) + { + *optimizedp = 0; + *lvalp = not_lval; + *addrp = 0; + *realnump = -1; + if (bufferp) + store_unsigned_integer (bufferp, reg_size, frame_base); + } + + /* If prologue analysis says we saved this register somewhere, + return a description of the stack slot holding it. */ + else if (p->reg_offset[regnum] != 1) + { + *optimizedp = 0; + *lvalp = lval_memory; + *addrp = frame_base + p->reg_offset[regnum]; + *realnump = -1; + if (bufferp) + get_frame_memory (next_frame, *addrp, bufferp, reg_size); + } + + /* Otherwise, presume we haven't changed the value of this + register, and get it from the next frame. */ + else + frame_register_unwind (next_frame, regnum, + optimizedp, lvalp, addrp, realnump, bufferp); +} + + +static const struct frame_unwind m32c_unwind = { + NORMAL_FRAME, + m32c_this_id, + m32c_prev_register +}; + + +static const struct frame_unwind * +m32c_frame_sniffer (struct frame_info *next_frame) +{ + return &m32c_unwind; +} + + +static CORE_ADDR +m32c_unwind_pc (struct gdbarch *arch, struct frame_info *next_frame) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + return frame_unwind_register_unsigned (next_frame, tdep->pc->num); +} + + +static CORE_ADDR +m32c_unwind_sp (struct gdbarch *arch, struct frame_info *next_frame) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (arch); + return frame_unwind_register_unsigned (next_frame, tdep->sp->num); +} + + +/* Inferior calls. */ + +/* The calling conventions, according to GCC: + + r8c, m16c + --------- + First arg may be passed in r1l or r1 if it (1) fits (QImode or + HImode), (2) is named, and (3) is an integer or pointer type (no + structs, floats, etc). Otherwise, it's passed on the stack. + + Second arg may be passed in r2, same restrictions (but not QImode), + even if the first arg is passed on the stack. + + Third and further args are passed on the stack. No padding is + used, stack "alignment" is 8 bits. + + m32cm, m32c + ----------- + + First arg may be passed in r0l or r0, same restrictions as above. + + Second and further args are passed on the stack. Padding is used + after QImode parameters (i.e. lower-addressed byte is the value, + higher-addressed byte is the padding), stack "alignment" is 16 + bits. */ + + +/* Return true if TYPE is a type that can be passed in registers. (We + ignore the size, and pay attention only to the type code; + acceptable sizes depends on which register is being considered to + hold it.) */ +static int +m32c_reg_arg_type (struct type *type) +{ + enum type_code code = TYPE_CODE (type); + + return (code == TYPE_CODE_INT + || code == TYPE_CODE_ENUM + || code == TYPE_CODE_PTR + || code == TYPE_CODE_REF + || code == TYPE_CODE_BOOL + || code == TYPE_CODE_CHAR); +} + + +static CORE_ADDR +m32c_push_dummy_call (struct gdbarch *gdbarch, struct value *function, + struct regcache *regcache, CORE_ADDR bp_addr, int nargs, + struct value **args, CORE_ADDR sp, int struct_return, + CORE_ADDR struct_addr) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach; + CORE_ADDR cfa; + int i; + + /* The number of arguments given in this function's prototype, or + zero if it has a non-prototyped function type. The m32c ABI + passes arguments mentioned in the prototype differently from + those in the ellipsis of a varargs function, or from those passed + to a non-prototyped function. */ + int num_prototyped_args = 0; + + { + struct type *func_type = value_type (function); + + gdb_assert (TYPE_CODE (func_type) == TYPE_CODE_FUNC || + TYPE_CODE (func_type) == TYPE_CODE_METHOD); + +#if 0 + /* The ABI description in gcc/config/m32c/m32c.abi says that + we need to handle prototyped and non-prototyped functions + separately, but the code in GCC doesn't actually do so. */ + if (TYPE_PROTOTYPED (func_type)) +#endif + num_prototyped_args = TYPE_NFIELDS (func_type); + } + + /* First, if the function returns an aggregate by value, push a + pointer to a buffer for it. This doesn't affect the way + subsequent arguments are allocated to registers. */ + if (struct_return) + { + int ptr_len = TYPE_LENGTH (tdep->ptr_voyd); + sp -= ptr_len; + write_memory_unsigned_integer (sp, ptr_len, struct_addr); + } + + /* Push the arguments. */ + for (i = nargs - 1; i >= 0; i--) + { + struct value *arg = args[i]; + const gdb_byte *arg_bits = value_contents (arg); + struct type *arg_type = value_type (arg); + ULONGEST arg_size = TYPE_LENGTH (arg_type); + + /* Can it go in r1 or r1l (for m16c) or r0 or r0l (for m32c)? */ + if (i == 0 + && arg_size <= 2 + && i < num_prototyped_args + && m32c_reg_arg_type (arg_type)) + { + /* Extract and re-store as an integer as a terse way to make + sure it ends up in the least significant end of r1. (GDB + should avoid assuming endianness, even on uni-endian + processors.) */ + ULONGEST u = extract_unsigned_integer (arg_bits, arg_size); + struct m32c_reg *reg = (mach == bfd_mach_m16c) ? tdep->r1 : tdep->r0; + regcache_cooked_write_unsigned (regcache, reg->num, u); + } + + /* Can it go in r2? */ + else if (mach == bfd_mach_m16c + && i == 1 + && arg_size == 2 + && i < num_prototyped_args + && m32c_reg_arg_type (arg_type)) + regcache_cooked_write (regcache, tdep->r2->num, arg_bits); + + /* Everything else goes on the stack. */ + else + { + sp -= arg_size; + + /* Align the stack. */ + if (mach == bfd_mach_m32c) + sp &= ~1; + + write_memory (sp, arg_bits, arg_size); + } + } + + /* This is the CFA we use to identify the dummy frame. */ + cfa = sp; + + /* Push the return address. */ + sp -= tdep->ret_addr_bytes; + write_memory_unsigned_integer (sp, tdep->ret_addr_bytes, bp_addr); + + /* Update the stack pointer. */ + regcache_cooked_write_unsigned (regcache, tdep->sp->num, sp); + + /* We need to borrow an odd trick from the i386 target here. + + The value we return from this function gets used as the stack + address (the CFA) for the dummy frame's ID. The obvious thing is + to return the new TOS. However, that points at the return + address, saved on the stack, which is inconsistent with the CFA's + described by GCC's DWARF 2 .debug_frame information: DWARF 2 + .debug_frame info uses the address immediately after the saved + return address. So you end up with a dummy frame whose CFA + points at the return address, but the frame for the function + being called has a CFA pointing after the return address: the + younger CFA is *greater than* the older CFA. The sanity checks + in frame.c don't like that. + + So we try to be consistent with the CFA's used by DWARF 2. + Having a dummy frame and a real frame with the *same* CFA is + tolerable. */ + return cfa; +} + + +static struct frame_id +m32c_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame) +{ + /* This needs to return a frame ID whose PC is the return address + passed to m32c_push_dummy_call, and whose stack_addr is the SP + m32c_push_dummy_call returned. + + m32c_unwind_sp gives us the CFA, which is the value the SP had + before the return address was pushed. */ + return frame_id_build (m32c_unwind_sp (gdbarch, next_frame), + frame_pc_unwind (next_frame)); +} + + + +/* Return values. */ + +/* Return value conventions, according to GCC: + + r8c, m16c + --------- + + QImode in r0l + HImode in r0 + SImode in r2r0 + near pointer in r0 + far pointer in r2r0 + + Aggregate values (regardless of size) are returned by pushing a + pointer to a temporary area on the stack after the args are pushed. + The function fills in this area with the value. Note that this + pointer on the stack does not affect how register arguments, if any, + are configured. + + m32cm, m32c + ----------- + Same. */ + +/* Return non-zero if values of type TYPE are returned by storing them + in a buffer whose address is passed on the stack, ahead of the + other arguments. */ +static int +m32c_return_by_passed_buf (struct type *type) +{ + enum type_code code = TYPE_CODE (type); + + return (code == TYPE_CODE_STRUCT + || code == TYPE_CODE_UNION); +} + +static enum return_value_convention +m32c_return_value (struct gdbarch *gdbarch, + struct type *valtype, + struct regcache *regcache, + gdb_byte *readbuf, + const gdb_byte *writebuf) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + enum return_value_convention conv; + ULONGEST valtype_len = TYPE_LENGTH (valtype); + + if (m32c_return_by_passed_buf (valtype)) + conv = RETURN_VALUE_STRUCT_CONVENTION; + else + conv = RETURN_VALUE_REGISTER_CONVENTION; + + if (readbuf) + { + /* We should never be called to find values being returned by + RETURN_VALUE_STRUCT_CONVENTION. Those can't be located, + unless we made the call ourselves. */ + gdb_assert (conv == RETURN_VALUE_REGISTER_CONVENTION); + + gdb_assert (valtype_len <= 8); + + /* Anything that fits in r0 is returned there. */ + if (valtype_len <= TYPE_LENGTH (tdep->r0->type)) + { + ULONGEST u; + regcache_cooked_read_unsigned (regcache, tdep->r0->num, &u); + store_unsigned_integer (readbuf, valtype_len, u); + } + else + { + /* Everything else is passed in mem0, using as many bytes as + needed. This is not what the Renesas tools do, but it's + what GCC does at the moment. */ + struct minimal_symbol *mem0 + = lookup_minimal_symbol ("mem0", NULL, NULL); + + if (! mem0) + error ("The return value is stored in memory at 'mem0', " + "but GDB cannot find\n" + "its address."); + read_memory (SYMBOL_VALUE_ADDRESS (mem0), readbuf, valtype_len); + } + } + + if (writebuf) + { + /* We should never be called to store values to be returned + using RETURN_VALUE_STRUCT_CONVENTION. We have no way of + finding the buffer, unless we made the call ourselves. */ + gdb_assert (conv == RETURN_VALUE_REGISTER_CONVENTION); + + gdb_assert (valtype_len <= 8); + + /* Anything that fits in r0 is returned there. */ + if (valtype_len <= TYPE_LENGTH (tdep->r0->type)) + { + ULONGEST u = extract_unsigned_integer (writebuf, valtype_len); + regcache_cooked_write_unsigned (regcache, tdep->r0->num, u); + } + else + { + /* Everything else is passed in mem0, using as many bytes as + needed. This is not what the Renesas tools do, but it's + what GCC does at the moment. */ + struct minimal_symbol *mem0 + = lookup_minimal_symbol ("mem0", NULL, NULL); + + if (! mem0) + error ("The return value is stored in memory at 'mem0', " + "but GDB cannot find\n" + " its address."); + write_memory (SYMBOL_VALUE_ADDRESS (mem0), + (char *) writebuf, valtype_len); + } + } + + return conv; +} + + + +/* Trampolines. */ + +/* The m16c and m32c use a trampoline function for indirect function + calls. An indirect call looks like this: + + ... push arguments ... + ... push target function address ... + jsr.a m32c_jsri16 + + The code for m32c_jsri16 looks like this: + + m32c_jsri16: + + # Save return address. + pop.w m32c_jsri_ret + pop.b m32c_jsri_ret+2 + + # Store target function address. + pop.w m32c_jsri_addr + + # Re-push return address. + push.b m32c_jsri_ret+2 + push.w m32c_jsri_ret + + # Call the target function. + jmpi.a m32c_jsri_addr + + Without further information, GDB will treat calls to m32c_jsri16 + like calls to any other function. Since m32c_jsri16 doesn't have + debugging information, that normally means that GDB sets a step- + resume breakpoint and lets the program continue --- which is not + what the user wanted. (Giving the trampoline debugging info + doesn't help: the user expects the program to stop in the function + their program is calling, not in some trampoline code they've never + seen before.) + + The SKIP_TRAMPOLINE_CODE gdbarch method tells GDB how to step + through such trampoline functions transparently to the user. When + given the address of a trampoline function's first instruction, + SKIP_TRAMPOLINE_CODE should return the address of the first + instruction of the function really being called. If GDB decides it + wants to step into that function, it will set a breakpoint there + and silently continue to it. + + We recognize the trampoline by name, and extract the target address + directly from the stack. This isn't great, but recognizing by its + code sequence seems more fragile. */ + +static CORE_ADDR +m32c_skip_trampoline_code (CORE_ADDR stop_pc) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + + /* It would be nicer to simply look up the addresses of known + trampolines once, and then compare stop_pc with them. However, + we'd need to ensure that that cached address got invalidated when + someone loaded a new executable, and I'm not quite sure of the + best way to do that. find_pc_partial_function does do some + caching, so we'll see how this goes. */ + char *name; + CORE_ADDR start, end; + + if (find_pc_partial_function (stop_pc, &name, &start, &end)) + { + /* Are we stopped at the beginning of the trampoline function? */ + if (strcmp (name, "m32c_jsri16") == 0 + && stop_pc == start) + { + /* Get the stack pointer. The return address is at the top, + and the target function's address is just below that. We + know it's a two-byte address, since the trampoline is + m32c_jsri*16*. */ + CORE_ADDR sp = get_frame_sp (get_current_frame ()); + CORE_ADDR target + = read_memory_unsigned_integer (sp + tdep->ret_addr_bytes, 2); + + /* What we have now is the address of a jump instruction. + What we need is the destination of that jump. + The opcode is 1 byte, and the destination is the next 3 bytes. + */ + target = read_memory_unsigned_integer (target + 1, 3); + return target; + } + } + + return 0; +} + + +/* Address/pointer conversions. */ + +/* On the m16c, there is a 24-bit address space, but only a very few + instructions can generate addresses larger than 0xffff: jumps, + jumps to subroutines, and the lde/std (load/store extended) + instructions. + + Since GCC can only support one size of pointer, we can't have + distinct 'near' and 'far' pointer types; we have to pick one size + for everything. If we wanted to use 24-bit pointers, then GCC + would have to use lde and ste for all memory references, which + would be terrible for performance and code size. So the GNU + toolchain uses 16-bit pointers for everything, and gives up the + ability to have pointers point outside the first 64k of memory. + + However, as a special hack, we let the linker place functions at + addresses above 0xffff, as long as it also places a trampoline in + the low 64k for every function whose address is taken. Each + trampoline consists of a single jmp.a instruction that jumps to the + function's real entry point. Pointers to functions can be 16 bits + long, even though the functions themselves are at higher addresses: + the pointers refer to the trampolines, not the functions. + + This complicates things for GDB, however: given the address of a + function (from debug info or linker symbols, say) which could be + anywhere in the 24-bit address space, how can we find an + appropriate 16-bit value to use as a pointer to it? + + If the linker has not generated a trampoline for the function, + we're out of luck. Well, I guess we could malloc some space and + write a jmp.a instruction to it, but I'm not going to get into that + at the moment. + + If the linker has generated a trampoline for the function, then it + also emitted a symbol for the trampoline: if the function's linker + symbol is named NAME, then the function's trampoline's linker + symbol is named NAME.plt. + + So, given a code address: + - We try to find a linker symbol at that address. + - If we find such a symbol named NAME, we look for a linker symbol + named NAME.plt. + - If we find such a symbol, we assume it is a trampoline, and use + its address as the pointer value. + + And, given a function pointer: + - We try to find a linker symbol at that address named NAME.plt. + - If we find such a symbol, we look for a linker symbol named NAME. + - If we find that, we provide that as the function's address. + - If any of the above steps fail, we return the original address + unchanged; it might really be a function in the low 64k. + + See? You *knew* there was a reason you wanted to be a computer + programmer! :) */ + +static void +m32c_m16c_address_to_pointer (struct type *type, gdb_byte *buf, CORE_ADDR addr) +{ + gdb_assert (TYPE_CODE (type) == TYPE_CODE_PTR || + TYPE_CODE (type) == TYPE_CODE_REF); + + enum type_code target_code = TYPE_CODE (TYPE_TARGET_TYPE (type)); + + if (target_code == TYPE_CODE_FUNC || target_code == TYPE_CODE_METHOD) + { + /* Try to find a linker symbol at this address. */ + struct minimal_symbol *func_msym = lookup_minimal_symbol_by_pc (addr); + + if (! func_msym) + error ("Cannot convert code address %s to function pointer:\n" + "couldn't find a symbol at that address, to find trampoline.", + paddr_nz (addr)); + + char *func_name = SYMBOL_LINKAGE_NAME (func_msym); + char *tramp_name = xmalloc (strlen (func_name) + 5); + strcpy (tramp_name, func_name); + strcat (tramp_name, ".plt"); + + /* Try to find a linker symbol for the trampoline. */ + struct minimal_symbol *tramp_msym + = lookup_minimal_symbol (tramp_name, NULL, NULL); + + /* We've either got another copy of the name now, or don't need + the name any more. */ + xfree (tramp_name); + + if (! tramp_msym) + error ("Cannot convert code address %s to function pointer:\n" + "couldn't find trampoline named '%s.plt'.", + paddr_nz (addr), func_name); + + /* The trampoline's address is our pointer. */ + addr = SYMBOL_VALUE_ADDRESS (tramp_msym); + } + + store_unsigned_integer (buf, TYPE_LENGTH (type), addr); +} + + +static CORE_ADDR +m32c_m16c_pointer_to_address (struct type *type, const gdb_byte *buf) +{ + gdb_assert (TYPE_CODE (type) == TYPE_CODE_PTR || + TYPE_CODE (type) == TYPE_CODE_REF); + + CORE_ADDR ptr = extract_unsigned_integer (buf, TYPE_LENGTH (type)); + + enum type_code target_code = TYPE_CODE (TYPE_TARGET_TYPE (type)); + + if (target_code == TYPE_CODE_FUNC || target_code == TYPE_CODE_METHOD) + { + /* See if there is a minimal symbol at that address whose name is + "NAME.plt". */ + struct minimal_symbol *ptr_msym = lookup_minimal_symbol_by_pc (ptr); + + if (ptr_msym) + { + char *ptr_msym_name = SYMBOL_LINKAGE_NAME (ptr_msym); + int len = strlen (ptr_msym_name); + + if (len > 4 + && strcmp (ptr_msym_name + len - 4, ".plt") == 0) + { + /* We have a .plt symbol; try to find the symbol for the + corresponding function. + + Since the trampoline contains a jump instruction, we + could also just extract the jump's target address. I + don't see much advantage one way or the other. */ + char *func_name = xmalloc (len - 4 + 1); + memcpy (func_name, ptr_msym_name, len - 4); + func_name[len - 4] = '\0'; + struct minimal_symbol *func_msym + = lookup_minimal_symbol (func_name, NULL, NULL); + + /* If we do have such a symbol, return its value as the + function's true address. */ + if (func_msym) + ptr = SYMBOL_VALUE_ADDRESS (func_msym); + } + } + } + + return ptr; +} + + + +/* Initialization. */ + +static struct gdbarch * +m32c_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) +{ + struct gdbarch *arch; + struct gdbarch_tdep *tdep; + unsigned long mach = info.bfd_arch_info->mach; + + /* Find a candidate among the list of architectures we've created + already. */ + for (arches = gdbarch_list_lookup_by_info (arches, &info); + arches != NULL; + arches = gdbarch_list_lookup_by_info (arches->next, &info)) + return arches->gdbarch; + + tdep = xcalloc (1, sizeof (*tdep)); + arch = gdbarch_alloc (&info, tdep); + + /* Essential types. */ + make_types (arch); + + /* Address/pointer conversions. */ + if (mach == bfd_mach_m16c) + { + set_gdbarch_address_to_pointer (arch, m32c_m16c_address_to_pointer); + set_gdbarch_pointer_to_address (arch, m32c_m16c_pointer_to_address); + } + + /* Register set. */ + make_regs (arch); + + /* Disassembly. */ + set_gdbarch_print_insn (arch, print_insn_m32c); + + /* Breakpoints. */ + set_gdbarch_breakpoint_from_pc (arch, m32c_breakpoint_from_pc); + + /* Prologue analysis and unwinding. */ + set_gdbarch_inner_than (arch, core_addr_lessthan); + set_gdbarch_skip_prologue (arch, m32c_skip_prologue); + set_gdbarch_unwind_pc (arch, m32c_unwind_pc); + set_gdbarch_unwind_sp (arch, m32c_unwind_sp); +#if 0 + /* I'm dropping the dwarf2 sniffer because it has a few problems. + They may be in the dwarf2 cfi code in GDB, or they may be in + the debug info emitted by the upstream toolchain. I don't + know which, but I do know that the prologue analyzer works better. + MVS 04/13/06 + */ + frame_unwind_append_sniffer (arch, dwarf2_frame_sniffer); +#endif + frame_unwind_append_sniffer (arch, m32c_frame_sniffer); + + /* Inferior calls. */ + set_gdbarch_push_dummy_call (arch, m32c_push_dummy_call); + set_gdbarch_return_value (arch, m32c_return_value); + set_gdbarch_unwind_dummy_id (arch, m32c_unwind_dummy_id); + + /* Trampolines. */ + set_gdbarch_skip_trampoline_code (arch, m32c_skip_trampoline_code); + + return arch; +} + + +void +_initialize_m32c_tdep (void) +{ + register_gdbarch_init (bfd_arch_m32c, m32c_gdbarch_init); + + m32c_dma_reggroup = reggroup_new ("dma", USER_REGGROUP); +} -- 2.34.1