#include "gdbcmd.h"
#include "gdbcore.h"
#include "dis-asm.h"
+#include "symfile.h"
+#include "objfiles.h"
/* FIXME: Some of this code should perhaps be merged with mips-tdep.c. */
-#define VM_MIN_ADDRESS (CORE_ADDR)0x120000000
+/* FIXME: Put this declaration in frame.h. */
+extern struct obstack frame_cache_obstack;
\f
/* Forward declarations. */
static void
reinit_frame_cache_sfunc PARAMS ((char *, int, struct cmd_list_element *));
+static CORE_ADDR after_prologue PARAMS ((CORE_ADDR pc,
+ alpha_extra_func_info_t proc_desc));
+
+static int in_prologue PARAMS ((CORE_ADDR pc,
+ alpha_extra_func_info_t proc_desc));
+
/* Heuristic_proc_start may hunt through the text section for a long
time across a 2400 baud serial line. Allows the user to limit this
search. */
} *linked_proc_desc_table = NULL;
\f
-#define READ_FRAME_REG(fi, regno) read_next_frame_reg((fi)->next, regno)
+/* Guaranteed to set fci->saved_regs to some values (it never leaves it
+ NULL). */
+
+void
+alpha_find_saved_regs (fci)
+ FRAME fci;
+{
+ int ireg;
+ CORE_ADDR reg_position;
+ unsigned long mask;
+ alpha_extra_func_info_t proc_desc;
+ int returnreg;
+
+ fci->saved_regs = (struct frame_saved_regs *)
+ obstack_alloc (&frame_cache_obstack, sizeof(struct frame_saved_regs));
+ memset (fci->saved_regs, 0, sizeof (struct frame_saved_regs));
+
+ proc_desc = fci->proc_desc;
+ if (proc_desc == NULL)
+ /* I'm not sure how/whether this can happen. Normally when we can't
+ find a proc_desc, we "synthesize" one using heuristic_proc_desc
+ and set the saved_regs right away. */
+ return;
+
+ /* Fill in the offsets for the registers which gen_mask says
+ were saved. */
+
+ reg_position = fci->frame + PROC_REG_OFFSET (proc_desc);
+ mask = PROC_REG_MASK (proc_desc);
+
+ returnreg = PROC_PC_REG (proc_desc);
+
+ /* Note that RA is always saved first, regardless of it's actual
+ register number. */
+ if (mask & (1 << returnreg))
+ {
+ fci->saved_regs->regs[returnreg] = reg_position;
+ reg_position += 8;
+ mask &= ~(1 << returnreg); /* Clear bit for RA so we
+ don't save again later. */
+ }
+
+ for (ireg = 0; ireg <= 31 ; ++ireg)
+ if (mask & (1 << ireg))
+ {
+ fci->saved_regs->regs[ireg] = reg_position;
+ reg_position += 8;
+ }
+
+ /* Fill in the offsets for the registers which float_mask says
+ were saved. */
+
+ reg_position = fci->frame + PROC_FREG_OFFSET (proc_desc);
+ mask = PROC_FREG_MASK (proc_desc);
+
+ for (ireg = 0; ireg <= 31 ; ++ireg)
+ if (mask & (1 << ireg))
+ {
+ fci->saved_regs->regs[FP0_REGNUM+ireg] = reg_position;
+ reg_position += 8;
+ }
+
+ fci->saved_regs->regs[PC_REGNUM] = fci->saved_regs->regs[returnreg];
+}
static CORE_ADDR
read_next_frame_reg(fi, regno)
}
else if (regno == SP_REGNUM)
return fi->frame;
- else if (fi->saved_regs->regs[regno])
- return read_memory_integer(fi->saved_regs->regs[regno], 8);
+ else
+ {
+ if (fi->saved_regs == NULL)
+ alpha_find_saved_regs (fi);
+ if (fi->saved_regs->regs[regno])
+ return read_memory_integer(fi->saved_regs->regs[regno], 8);
+ }
}
return read_register(regno);
}
PROC_FRAME_OFFSET(&temp_proc_desc) = frame_size;
PROC_REG_MASK(&temp_proc_desc) = reg_mask;
PROC_PC_REG(&temp_proc_desc) = RA_REGNUM;
+ PROC_LOCALOFF(&temp_proc_desc) = 0; /* XXX - bogus */
return &temp_proc_desc;
}
+/* This returns the PC of the first inst after the prologue. If we can't
+ find the prologue, then return 0. */
+
+static CORE_ADDR
+after_prologue (pc, proc_desc)
+ CORE_ADDR pc;
+ alpha_extra_func_info_t proc_desc;
+{
+ struct block *b;
+ struct symtab_and_line sal;
+ CORE_ADDR func_addr, func_end;
+
+ if (!proc_desc)
+ proc_desc = find_proc_desc (pc, NULL);
+
+ if (proc_desc)
+ {
+ /* If function is frameless, then we need to do it the hard way. I
+ strongly suspect that frameless always means prologueless... */
+ if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
+ && PROC_FRAME_OFFSET (proc_desc) == 0)
+ return 0;
+ }
+
+ if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+ return 0; /* Unknown */
+
+ sal = find_pc_line (func_addr, 0);
+
+ if (sal.end < func_end)
+ return sal.end;
+
+ /* The line after the prologue is after the end of the function. In this
+ case, tell the caller to find the prologue the hard way. */
+
+ return 0;
+}
+
+/* Return non-zero if we *might* be in a function prologue. Return zero if we
+ are definatly *not* in a function prologue. */
+
+static int
+in_prologue (pc, proc_desc)
+ CORE_ADDR pc;
+ alpha_extra_func_info_t proc_desc;
+{
+ CORE_ADDR after_prologue_pc;
+
+ after_prologue_pc = after_prologue (pc, proc_desc);
+
+ if (after_prologue_pc == 0
+ || pc < after_prologue_pc)
+ return 1;
+ else
+ return 0;
+}
+
static alpha_extra_func_info_t
find_proc_desc(pc, next_frame)
CORE_ADDR pc;
as it will be contained in the proc_desc we are searching for.
So we have to find the proc_desc whose frame is closest to the current
stack pointer. */
+
if (PC_IN_CALL_DUMMY (pc, 0, 0))
{
struct linked_proc_info *link;
}
b = block_for_pc(pc);
+
find_pc_partial_function (pc, NULL, &startaddr, NULL);
if (b == NULL)
sym = NULL;
if (sym)
{
- /* IF (this is the topmost frame OR a frame interrupted by a signal)
- * AND (this proc does not have debugging information OR
+ /* IF this is the topmost frame AND
+ * (this proc does not have debugging information OR
* the PC is in the procedure prologue)
* THEN create a "heuristic" proc_desc (by analyzing
* the actual code) to replace the "official" proc_desc.
*/
proc_desc = (alpha_extra_func_info_t)SYMBOL_VALUE(sym);
- if (next_frame == NULL || next_frame->signal_handler_caller) {
- struct symtab_and_line val;
- struct symbol *proc_symbol =
- PROC_DESC_IS_DUMMY(proc_desc) ? 0 : PROC_SYMBOL(proc_desc);
-
- if (proc_symbol) {
- val = find_pc_line (BLOCK_START
- (SYMBOL_BLOCK_VALUE(proc_symbol)),
- 0);
- val.pc = val.end ? val.end : pc;
- }
- if (!proc_symbol || pc < val.pc) {
+ if (next_frame == NULL)
+ {
+ if (PROC_DESC_IS_DUMMY (proc_desc) || in_prologue (pc, proc_desc))
+ {
alpha_extra_func_info_t found_heuristic =
- heuristic_proc_desc(PROC_LOW_ADDR(proc_desc),
- pc, next_frame);
+ heuristic_proc_desc (PROC_LOW_ADDR (proc_desc),
+ pc, next_frame);
+ PROC_LOCALOFF (found_heuristic) = PROC_LOCALOFF (proc_desc);
if (found_heuristic)
- {
- /* The call to heuristic_proc_desc determines
- which registers have been saved so far and if the
- frame is already set up.
- The heuristic algorithm doesn't work well for other
- information in the procedure descriptor, so copy
- it from the found procedure descriptor. */
- PROC_LOCALOFF(found_heuristic) = PROC_LOCALOFF(proc_desc);
- PROC_PC_REG(found_heuristic) = PROC_PC_REG(proc_desc);
- proc_desc = found_heuristic;
- }
- }
- }
+ proc_desc = found_heuristic;
+ }
+ }
}
else
{
+ /* Is linked_proc_desc_table really necessary? It only seems to be used
+ by procedure call dummys. However, the procedures being called ought
+ to have their own proc_descs, and even if they don't,
+ heuristic_proc_desc knows how to create them! */
+
+ register struct linked_proc_info *link;
+ for (link = linked_proc_desc_table; link; link = link->next)
+ if (PROC_LOW_ADDR(&link->info) <= pc
+ && PROC_HIGH_ADDR(&link->info) > pc)
+ return &link->info;
+
if (startaddr == 0)
startaddr = heuristic_proc_start (pc);
init_extra_frame_info(fci)
struct frame_info *fci;
{
- extern struct obstack frame_cache_obstack;
/* Use proc_desc calculated in frame_chain */
alpha_extra_func_info_t proc_desc =
fci->next ? cached_proc_desc : find_proc_desc(fci->pc, fci->next);
- fci->saved_regs = (struct frame_saved_regs*)
- obstack_alloc (&frame_cache_obstack, sizeof(struct frame_saved_regs));
- memset (fci->saved_regs, 0, sizeof (struct frame_saved_regs));
+ fci->saved_regs = NULL;
fci->proc_desc =
proc_desc == &temp_proc_desc ? 0 : proc_desc;
if (proc_desc)
{
- int ireg;
- CORE_ADDR reg_position;
- unsigned long mask;
- int returnreg;
-
/* Get the locals offset from the procedure descriptor, it is valid
even if we are in the middle of the prologue. */
fci->localoff = PROC_LOCALOFF(proc_desc);
/* Fixup frame-pointer - only needed for top frame */
+
/* Fetch the frame pointer for a dummy frame from the procedure
descriptor. */
if (PROC_DESC_IS_DUMMY(proc_desc))
fci->frame = (FRAME_ADDR) PROC_DUMMY_FRAME(proc_desc);
+
/* This may not be quite right, if proc has a real frame register.
Get the value of the frame relative sp, procedure might have been
interrupted by a signal at it's very start. */
- else if (fci->pc == PROC_LOW_ADDR(proc_desc))
- fci->frame = READ_FRAME_REG(fci, SP_REGNUM);
+ else if (fci->pc == PROC_LOW_ADDR (proc_desc) && !PROC_DESC_IS_DUMMY (proc_desc))
+ fci->frame = read_next_frame_reg (fci->next, SP_REGNUM);
else
- fci->frame = READ_FRAME_REG(fci, PROC_FRAME_REG(proc_desc))
- + PROC_FRAME_OFFSET(proc_desc);
-
- /* If this is the innermost frame, and we are still in the
- prologue (loosely defined), then the registers may not have
- been saved yet. */
- if (fci->next == NULL
- && !PROC_DESC_IS_DUMMY(proc_desc)
- && alpha_in_lenient_prologue (PROC_LOW_ADDR (proc_desc), fci->pc))
- {
- /* Can't just say that the registers are not saved, because they
- might get clobbered halfway through the prologue.
- heuristic_proc_desc already has the right code to figure out
- exactly what has been saved, so use it. As far as I know we
- could be doing this (as we do on the 68k, for example)
- regardless of whether we are in the prologue; I'm leaving in
- the check for being in the prologue only out of conservatism
- (I'm not sure whether heuristic_proc_desc handles all cases,
- for example).
-
- This stuff is ugly (and getting uglier by the minute). Probably
- the best way to clean it up is to ignore the proc_desc's from
- the symbols altogher, and get all the information we need by
- examining the prologue (provided we can make the prologue
- examining code good enough to get all the cases...). */
- proc_desc =
- heuristic_proc_desc (PROC_LOW_ADDR (proc_desc),
- fci->pc,
- fci->next);
- }
+ fci->frame = read_next_frame_reg (fci->next, PROC_FRAME_REG (proc_desc))
+ + PROC_FRAME_OFFSET (proc_desc);
if (proc_desc == &temp_proc_desc)
- *fci->saved_regs = temp_saved_regs;
- else
{
- /* Find which general-purpose registers were saved.
- The return address register is the first saved register,
- the other registers follow in ascending order. */
- reg_position = fci->frame + PROC_REG_OFFSET(proc_desc);
- mask = PROC_REG_MASK(proc_desc) & 0xffffffffL;
- returnreg = PROC_PC_REG(proc_desc);
- if (mask & (1 << returnreg))
- {
- fci->saved_regs->regs[returnreg] = reg_position;
- reg_position += 8;
- }
- for (ireg = 0; mask; ireg++, mask >>= 1)
- if (mask & 1)
- {
- if (ireg == returnreg)
- continue;
- fci->saved_regs->regs[ireg] = reg_position;
- reg_position += 8;
- }
- /* find which floating-point registers were saved */
- reg_position = fci->frame + PROC_FREG_OFFSET(proc_desc);
- mask = PROC_FREG_MASK(proc_desc) & 0xffffffffL;
- for (ireg = 0; mask; ireg++, mask >>= 1)
- if (mask & 1)
- {
- fci->saved_regs->regs[FP0_REGNUM+ireg] = reg_position;
- reg_position += 8;
- }
+ fci->saved_regs = (struct frame_saved_regs*)
+ obstack_alloc (&frame_cache_obstack,
+ sizeof (struct frame_saved_regs));
+ *fci->saved_regs = temp_saved_regs;
+ fci->saved_regs->regs[PC_REGNUM] = fci->saved_regs->regs[RA_REGNUM];
}
-
- fci->saved_regs->regs[PC_REGNUM] = fci->saved_regs->regs[PROC_PC_REG(proc_desc)];
}
}
alpha_push_dummy_frame()
{
int ireg;
- struct linked_proc_info *link = (struct linked_proc_info*)
- xmalloc(sizeof (struct linked_proc_info));
- alpha_extra_func_info_t proc_desc = &link->info;
+ struct linked_proc_info *link;
+ alpha_extra_func_info_t proc_desc;
CORE_ADDR sp = read_register (SP_REGNUM);
CORE_ADDR save_address;
char raw_buffer[MAX_REGISTER_RAW_SIZE];
unsigned long mask;
+ link = (struct linked_proc_info *) xmalloc(sizeof (struct linked_proc_info));
link->next = linked_proc_desc_table;
linked_proc_desc_table = link;
+
+ proc_desc = &link->info;
/*
* The registers we must save are all those not preserved across
sp += PROC_REG_OFFSET(proc_desc);
write_register (SP_REGNUM, sp);
- PROC_LOW_ADDR(proc_desc) = entry_point_address ();
+ PROC_LOW_ADDR(proc_desc) = CALL_DUMMY_ADDRESS ();
PROC_HIGH_ADDR(proc_desc) = PROC_LOW_ADDR(proc_desc) + 4;
SET_PROC_DESC_IS_DUMMY(proc_desc);
alpha_extra_func_info_t proc_desc = frame->proc_desc;
write_register (PC_REGNUM, FRAME_SAVED_PC(frame));
+ if (frame->saved_regs == NULL)
+ alpha_find_saved_regs (frame);
if (proc_desc)
{
for (regnum = 32; --regnum >= 0; )
{
unsigned long inst;
int offset;
+ CORE_ADDR post_prologue_pc;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+
+ post_prologue_pc = after_prologue (pc, NULL);
+
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
/* Skip the typical prologue instructions. These are the stack adjustment
instruction and the instructions that save registers on the stack
reinit_frame_cache ();
}
+/* This is the definition of CALL_DUMMY_ADDRESS. It's a heuristic that is used
+ to find a convenient place in the text segment to stick a breakpoint to
+ detect the completion of a target function call (ala call_function_by_hand).
+ */
+
+CORE_ADDR
+alpha_call_dummy_address ()
+{
+ CORE_ADDR entry;
+ struct minimal_symbol *sym;
+
+ entry = entry_point_address ();
+
+ if (entry != 0)
+ return entry;
+
+ sym = lookup_minimal_symbol ("_Prelude", symfile_objfile);
+
+ if (!sym || MSYMBOL_TYPE (sym) != mst_text)
+ return 0;
+ else
+ return SYMBOL_VALUE_ADDRESS (sym) + 4;
+}
+
void
_initialize_alpha_tdep ()
{
projects / deliverable / binutils-gdb.git / blobdiff