/* These the fields of 32 bit mips instructions */
-#define mips32_op(x) (x >> 25)
-#define itype_op(x) (x >> 25)
-#define itype_rs(x) ((x >> 21)& 0x1f)
+#define mips32_op(x) (x >> 26)
+#define itype_op(x) (x >> 26)
+#define itype_rs(x) ((x >> 21) & 0x1f)
#define itype_rt(x) ((x >> 16) & 0x1f)
-#define itype_immediate(x) ( x & 0xffff)
+#define itype_immediate(x) (x & 0xffff)
-#define jtype_op(x) (x >> 25)
-#define jtype_target(x) ( x & 0x03fffff)
+#define jtype_op(x) (x >> 26)
+#define jtype_target(x) (x & 0x03ffffff)
-#define rtype_op(x) (x >>25)
-#define rtype_rs(x) ((x>>21) & 0x1f)
-#define rtype_rt(x) ((x>>16) & 0x1f)
-#define rtype_rd(x) ((x>>11) & 0x1f)
-#define rtype_shamt(x) ((x>>6) & 0x1f)
-#define rtype_funct(x) (x & 0x3f )
+#define rtype_op(x) (x >> 26)
+#define rtype_rs(x) ((x >> 21) & 0x1f)
+#define rtype_rt(x) ((x >> 16) & 0x1f)
+#define rtype_rd(x) ((x >> 11) & 0x1f)
+#define rtype_shamt(x) ((x >> 6) & 0x1f)
+#define rtype_funct(x) (x & 0x3f)
static CORE_ADDR
mips32_relative_offset (unsigned long inst)
unsigned long inst;
int op;
inst = mips_fetch_instruction (pc);
- if ((inst & 0xe0000000) != 0) /* Not a special, junp or branch instruction */
+ if ((inst & 0xe0000000) != 0) /* Not a special, jump or branch instruction */
{
- if ((inst >> 27) == 5) /* BEQL BNEZ BLEZL BGTZE , bits 0101xx */
+ if (itype_op (inst) >> 2 == 5)
+ /* BEQL, BNEL, BLEZL, BGTZL: bits 0101xx */
{
- op = ((inst >> 25) & 0x03);
+ op = (itype_op (inst) & 0x03);
switch (op)
{
- case 0:
- goto equal_branch; /* BEQL */
- case 1:
- goto neq_branch; /* BNEZ */
- case 2:
- goto less_branch; /* BLEZ */
- case 3:
- goto greater_branch; /* BGTZ */
+ case 0: /* BEQL */
+ goto equal_branch;
+ case 1: /* BNEL */
+ goto neq_branch;
+ case 2: /* BLEZL */
+ goto less_branch;
+ case 3: /* BGTZ */
+ goto greater_branch;
default:
pc += 4;
}
}
+ else if (itype_op (inst) == 17 && itype_rs (inst) == 8)
+ /* BC1F, BC1FL, BC1T, BC1TL: 010001 01000 */
+ {
+ int tf = itype_rt (inst) & 0x01;
+ int cnum = itype_rt (inst) >> 2;
+ int fcrcs = read_signed_register (FCRCS_REGNUM);
+ int cond = ((fcrcs >> 24) & 0x0e) | ((fcrcs >> 23) & 0x01);
+
+ if (((cond >> cnum) & 0x01) == tf)
+ pc += mips32_relative_offset (inst) + 4;
+ else
+ pc += 8;
+ }
else
pc += 4; /* Not a branch, next instruction is easy */
}
{ /* This gets way messy */
/* Further subdivide into SPECIAL, REGIMM and other */
- switch (op = ((inst >> 26) & 0x07)) /* extract bits 28,27,26 */
+ switch (op = itype_op (inst) & 0x07) /* extract bits 28,27,26 */
{
case 0: /* SPECIAL */
op = rtype_funct (inst);
pc += 4;
}
- break; /* end special */
+ break; /* end SPECIAL */
case 1: /* REGIMM */
{
- op = jtype_op (inst); /* branch condition */
- switch (jtype_op (inst))
+ op = itype_rt (inst); /* branch condition */
+ switch (op)
{
case 0: /* BLTZ */
- case 2: /* BLTXL */
- case 16: /* BLTZALL */
+ case 2: /* BLTZL */
+ case 16: /* BLTZAL */
case 18: /* BLTZALL */
less_branch:
if (read_signed_register (itype_rs (inst)) < 0)
else
pc += 8; /* after the delay slot */
break;
- case 1: /* GEZ */
+ case 1: /* BGEZ */
case 3: /* BGEZL */
case 17: /* BGEZAL */
case 19: /* BGEZALL */
else
pc += 8; /* after the delay slot */
break;
- /* All of the other intructions in the REGIMM catagory */
+ /* All of the other instructions in the REGIMM category */
default:
pc += 4;
}
}
- break; /* end REGIMM */
+ break; /* end REGIMM */
case 2: /* J */
case 3: /* JAL */
{
unsigned long reg;
reg = jtype_target (inst) << 2;
+ /* Upper four bits get never changed... */
pc = reg + ((pc + 4) & 0xf0000000);
- /* Whats this mysterious 0xf000000 adjustment ??? */
}
break;
/* FIXME case JALX : */
/* Add 1 to indicate 16 bit mode - Invert ISA mode */
}
break; /* The new PC will be alternate mode */
- case 4: /* BEQ , BEQL */
+ case 4: /* BEQ, BEQL */
equal_branch:
if (read_signed_register (itype_rs (inst)) ==
read_signed_register (itype_rt (inst)))
else
pc += 8;
break;
- case 5: /* BNE , BNEL */
+ case 5: /* BNE, BNEL */
neq_branch:
if (read_signed_register (itype_rs (inst)) !=
- read_signed_register (itype_rs (inst)))
+ read_signed_register (itype_rt (inst)))
pc += mips32_relative_offset (inst) + 4;
else
pc += 8;
break;
- case 6: /* BLEZ , BLEZL */
+ case 6: /* BLEZ, BLEZL */
less_zero_branch:
if (read_signed_register (itype_rs (inst) <= 0))
pc += mips32_relative_offset (inst) + 4;
pc += 8;
break;
case 7:
- greater_branch: /* BGTZ BGTZL */
+ default:
+ greater_branch: /* BGTZ, BGTZL */
if (read_signed_register (itype_rs (inst) > 0))
pc += mips32_relative_offset (inst) + 4;
else
pc += 8;
break;
- default:
- pc += 8;
} /* switch */
} /* else */
return pc;
return addr;
}
+/* mips_software_single_step() is called just before we want to resume
+ the inferior, if we want to single-step it but there is no hardware
+ or kernel single-step support (MIPS on Linux for example). We find
+ the target of the coming instruction and breakpoint it.
+
+ single_step is also called just after the inferior stops. If we had
+ set up a simulated single-step, we undo our damage. */
+
+void
+mips_software_single_step (enum target_signal sig, int insert_breakpoints_p)
+{
+ static CORE_ADDR next_pc;
+ typedef char binsn_quantum[BREAKPOINT_MAX];
+ static binsn_quantum break_mem;
+ CORE_ADDR pc;
+
+ if (insert_breakpoints_p)
+ {
+ pc = read_register (PC_REGNUM);
+ next_pc = mips_next_pc (pc);
+
+ target_insert_breakpoint (next_pc, break_mem);
+ }
+ else
+ target_remove_breakpoint (next_pc, break_mem);
+}
+
static void
mips_init_frame_pc_first (int fromleaf, struct frame_info *prev)
{
&& MIPS_FPU_TYPE != MIPS_FPU_NONE);
}
+/* On o32, argument passing in GPRs depends on the alignment of the type being
+ passed. Return 1 if this type must be aligned to a doubleword boundary. */
+
+static int
+mips_type_needs_double_align (struct type *type)
+{
+ enum type_code typecode = TYPE_CODE (type);
+
+ if (typecode == TYPE_CODE_FLT && TYPE_LENGTH (type) == 8)
+ return 1;
+ else if (typecode == TYPE_CODE_STRUCT)
+ {
+ if (TYPE_NFIELDS (type) < 1)
+ return 0;
+ return mips_type_needs_double_align (TYPE_FIELD_TYPE (type, 0));
+ }
+ else if (typecode == TYPE_CODE_UNION)
+ {
+ int i, n;
+
+ n = TYPE_NFIELDS (type);
+ for (i = 0; i < n; i++)
+ if (mips_type_needs_double_align (TYPE_FIELD_TYPE (type, i)))
+ return 1;
+ return 0;
+ }
+ return 0;
+}
+
CORE_ADDR
mips_push_arguments (int nargs,
- value_ptr *args,
+ struct value **args,
CORE_ADDR sp,
int struct_return,
CORE_ADDR struct_addr)
{
char *val;
char valbuf[MAX_REGISTER_RAW_SIZE];
- value_ptr arg = args[argnum];
+ struct value *arg = args[argnum];
struct type *arg_type = check_typedef (VALUE_TYPE (arg));
int len = TYPE_LENGTH (arg_type);
enum type_code typecode = TYPE_CODE (arg_type);
compatibility, we will put them in both places. */
int odd_sized_struct = ((len > MIPS_SAVED_REGSIZE) &&
(len % MIPS_SAVED_REGSIZE != 0));
+ /* Structures should be aligned to eight bytes (even arg registers)
+ on MIPS_ABI_O32 if their first member has double precision. */
+ if (gdbarch_tdep (current_gdbarch)->mips_abi == MIPS_ABI_O32
+ && mips_type_needs_double_align (arg_type))
+ {
+ if ((argreg & 1))
+ argreg++;
+ }
/* Note: Floating-point values that didn't fit into an FP
register are only written to memory. */
while (len > 0)
same for integral types.
Also don't do this adjustment on EABI and O64
- binaries. */
+ binaries.
+
+ cagney/2001-07-23: gdb/179: Also, GCC, when
+ outputting LE O32 with sizeof (struct) <
+ MIPS_SAVED_REGSIZE, generates a left shift as
+ part of storing the argument in a register a
+ register (the left shift isn't generated when
+ sizeof (struct) >= MIPS_SAVED_REGSIZE). Since it
+ is quite possible that this is GCC contradicting
+ the LE/O32 ABI, GDB has not been adjusted to
+ accommodate this. Either someone needs to
+ demonstrate that the LE/O32 ABI specifies such a
+ left shift OR this new ABI gets identified as
+ such and GDB gets tweaked accordingly. */
if (!MIPS_EABI
&& MIPS_SAVED_REGSIZE < 8
/* There's a mess in stack frame creation. See comments in
blockframe.c near reference to INIT_FRAME_PC_FIRST. */
set_gdbarch_init_frame_pc_first (gdbarch, mips_init_frame_pc_first);
+ set_gdbarch_init_frame_pc (gdbarch, init_frame_pc_noop);
/* Map debug register numbers onto internal register numbers. */
set_gdbarch_stab_reg_to_regnum (gdbarch, mips_stab_reg_to_regnum);
projects / deliverable / binutils-gdb.git / blobdiff