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[commit] Make MIPS set_reg_offset explicit
- From: Andrew Cagney <ac131313 at redhat dot com>
- To: gdb-patches at sources dot redhat dot com
- Date: Sat, 31 May 2003 21:38:20 -0400
- Subject: [commit] Make MIPS set_reg_offset explicit
Hello,
This patch cleans up a little bit of the MIPS frame find saved regs code:
- adds a explicit parameter to set_reg_offset.
- eliminates a redundant wrapper function.
committed,
Andrew
2003-05-31 Andrew Cagney <cagney@redhat.com>
* mips-tdep.c (set_reg_offset): Add saved_regs parameter. Add
forward declaration.
(mips16_heuristic_proc_desc): Pass temp_saved_regs.
(mips16_heuristic_proc_desc): Pass temp_saved_regs.
(mips_find_saved_regs): Use set_reg_offset.
(mips_frame_init_saved_regs): Delete function.
(mips_pop_frame): Call mips_find_saved_regs instead of
DEPRECATED_FRAME_INIT_SAVED_REGS.
Index: mips-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/mips-tdep.c,v
retrieving revision 1.204
diff -u -r1.204 mips-tdep.c
--- mips-tdep.c 31 May 2003 22:56:29 -0000 1.204
+++ mips-tdep.c 1 Jun 2003 01:26:58 -0000
@@ -48,6 +48,8 @@
#include "elf-bfd.h"
#include "symcat.h"
+static void set_reg_offset (CORE_ADDR *saved_regs, int regnum, CORE_ADDR off);
+
/* A useful bit in the CP0 status register (PS_REGNUM). */
/* This bit is set if we are emulating 32-bit FPRs on a 64-bit chip. */
#define ST0_FR (1 << 26)
@@ -1423,38 +1425,37 @@
return mips32_next_pc (pc);
}
-/* Guaranteed to set fci->saved_regs to some values (it never leaves it
- NULL).
-
- Note: kevinb/2002-08-09: The only caller of this function is (and
- should remain) mips_frame_init_saved_regs(). In fact,
- aside from calling mips_find_saved_regs(), mips_frame_init_saved_regs()
- does nothing more than set frame->saved_regs[SP_REGNUM]. These two
- functions should really be combined and now that there is only one
- caller, it should be straightforward. (Watch out for multiple returns
- though.) */
+/* Set up the 'saved_regs' array. This is a data structure containing
+ the addresses on the stack where each register has been saved, for
+ each stack frame. Registers that have not been saved will have
+ zero here. The stack pointer register is special: rather than the
+ address where the stack register has been saved,
+ saved_regs[SP_REGNUM] will have the actual value of the previous
+ frame's stack register. */
static void
mips_find_saved_regs (struct frame_info *fci)
{
int ireg;
- CORE_ADDR reg_position;
/* r0 bit means kernel trap */
int kernel_trap;
/* What registers have been saved? Bitmasks. */
unsigned long gen_mask, float_mask;
mips_extra_func_info_t proc_desc;
t_inst inst;
+ CORE_ADDR *saved_regs;
- frame_saved_regs_zalloc (fci);
+ if (get_frame_saved_regs (fci) != NULL)
+ return;
+ saved_regs = frame_saved_regs_zalloc (fci);
/* If it is the frame for sigtramp, the saved registers are located
- in a sigcontext structure somewhere on the stack.
- If the stack layout for sigtramp changes we might have to change these
- constants and the companion fixup_sigtramp in mdebugread.c */
+ in a sigcontext structure somewhere on the stack. If the stack
+ layout for sigtramp changes we might have to change these
+ constants and the companion fixup_sigtramp in mdebugread.c */
#ifndef SIGFRAME_BASE
-/* To satisfy alignment restrictions, sigcontext is located 4 bytes
- above the sigtramp frame. */
+ /* To satisfy alignment restrictions, sigcontext is located 4 bytes
+ above the sigtramp frame. */
#define SIGFRAME_BASE MIPS_REGSIZE
/* FIXME! Are these correct?? */
#define SIGFRAME_PC_OFF (SIGFRAME_BASE + 2 * MIPS_REGSIZE)
@@ -1463,61 +1464,65 @@
(SIGFRAME_REGSAVE_OFF + MIPS_NUMREGS * MIPS_REGSIZE + 3 * MIPS_REGSIZE)
#endif
#ifndef SIGFRAME_REG_SIZE
-/* FIXME! Is this correct?? */
+ /* FIXME! Is this correct?? */
#define SIGFRAME_REG_SIZE MIPS_REGSIZE
#endif
if ((get_frame_type (fci) == SIGTRAMP_FRAME))
{
for (ireg = 0; ireg < MIPS_NUMREGS; ireg++)
{
- reg_position = get_frame_base (fci) + SIGFRAME_REGSAVE_OFF
- + ireg * SIGFRAME_REG_SIZE;
- get_frame_saved_regs (fci)[ireg] = reg_position;
+ CORE_ADDR reg_position = (get_frame_base (fci) + SIGFRAME_REGSAVE_OFF
+ + ireg * SIGFRAME_REG_SIZE);
+ set_reg_offset (saved_regs, ireg, reg_position);
}
for (ireg = 0; ireg < MIPS_NUMREGS; ireg++)
{
- reg_position = get_frame_base (fci) + SIGFRAME_FPREGSAVE_OFF
- + ireg * SIGFRAME_REG_SIZE;
- get_frame_saved_regs (fci)[FP0_REGNUM + ireg] = reg_position;
+ CORE_ADDR reg_position = (get_frame_base (fci)
+ + SIGFRAME_FPREGSAVE_OFF
+ + ireg * SIGFRAME_REG_SIZE);
+ set_reg_offset (saved_regs, FP0_REGNUM + ireg, reg_position);
}
- get_frame_saved_regs (fci)[PC_REGNUM] = get_frame_base (fci) + SIGFRAME_PC_OFF;
+
+ set_reg_offset (saved_regs, PC_REGNUM, get_frame_base (fci) + SIGFRAME_PC_OFF);
+ /* SP_REGNUM, contains the value and not the address. */
+ set_reg_offset (saved_regs, SP_REGNUM, get_frame_base (fci));
return;
}
proc_desc = get_frame_extra_info (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. */
+ /* 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;
kernel_trap = PROC_REG_MASK (proc_desc) & 1;
gen_mask = kernel_trap ? 0xFFFFFFFF : PROC_REG_MASK (proc_desc);
float_mask = kernel_trap ? 0xFFFFFFFF : PROC_FREG_MASK (proc_desc);
- if ( /* In any frame other than the innermost or a frame interrupted by
- a signal, we assume that all registers have been saved.
- This assumes that all register saves in a function happen before
- the first function call. */
+ if (/* In any frame other than the innermost or a frame interrupted
+ by a signal, we assume that all registers have been saved.
+ This assumes that all register saves in a function happen
+ before the first function call. */
(get_next_frame (fci) == NULL
|| (get_frame_type (get_next_frame (fci)) == SIGTRAMP_FRAME))
- /* In a dummy frame we know exactly where things are saved. */
+ /* In a dummy frame we know exactly where things are saved. */
&& !PROC_DESC_IS_DUMMY (proc_desc)
- /* Don't bother unless we are inside a function prologue. Outside the
- prologue, we know where everything is. */
+ /* Don't bother unless we are inside a function prologue.
+ Outside the prologue, we know where everything is. */
&& in_prologue (get_frame_pc (fci), PROC_LOW_ADDR (proc_desc))
- /* Not sure exactly what kernel_trap means, but if it means
- the kernel saves the registers without a prologue doing it,
- we better not examine the prologue to see whether registers
- have been saved yet. */
+ /* Not sure exactly what kernel_trap means, but if it means the
+ kernel saves the registers without a prologue doing it, we
+ better not examine the prologue to see whether registers
+ have been saved yet. */
&& !kernel_trap)
{
- /* We need to figure out whether the registers that the proc_desc
- claims are saved have been saved yet. */
+ /* We need to figure out whether the registers that the
+ proc_desc claims are saved have been saved yet. */
CORE_ADDR addr;
@@ -1530,8 +1535,8 @@
addr = PROC_LOW_ADDR (proc_desc);
instlen = pc_is_mips16 (addr) ? MIPS16_INSTLEN : MIPS_INSTLEN;
- /* Scan through this function's instructions preceding the current
- PC, and look for those that save registers. */
+ /* Scan through this function's instructions preceding the
+ current PC, and look for those that save registers. */
while (addr < get_frame_pc (fci))
{
inst = mips_fetch_instruction (addr);
@@ -1545,89 +1550,84 @@
float_mask = float_save_found;
}
- /* Fill in the offsets for the registers which gen_mask says
- were saved. */
- reg_position = get_frame_base (fci) + PROC_REG_OFFSET (proc_desc);
- for (ireg = MIPS_NUMREGS - 1; gen_mask; --ireg, gen_mask <<= 1)
- if (gen_mask & 0x80000000)
- {
- get_frame_saved_regs (fci)[ireg] = reg_position;
- reg_position -= MIPS_SAVED_REGSIZE;
- }
+ /* Fill in the offsets for the registers which gen_mask says were
+ saved. */
+ {
+ CORE_ADDR reg_position = (get_frame_base (fci)
+ + PROC_REG_OFFSET (proc_desc));
+ for (ireg = MIPS_NUMREGS - 1; gen_mask; --ireg, gen_mask <<= 1)
+ if (gen_mask & 0x80000000)
+ {
+ set_reg_offset (saved_regs, ireg, reg_position);
+ reg_position -= MIPS_SAVED_REGSIZE;
+ }
+ }
- /* The MIPS16 entry instruction saves $s0 and $s1 in the reverse order
- of that normally used by gcc. Therefore, we have to fetch the first
- instruction of the function, and if it's an entry instruction that
- saves $s0 or $s1, correct their saved addresses. */
+ /* The MIPS16 entry instruction saves $s0 and $s1 in the reverse
+ order of that normally used by gcc. Therefore, we have to fetch
+ the first instruction of the function, and if it's an entry
+ instruction that saves $s0 or $s1, correct their saved addresses. */
if (pc_is_mips16 (PROC_LOW_ADDR (proc_desc)))
{
inst = mips_fetch_instruction (PROC_LOW_ADDR (proc_desc));
- if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
+ if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700)
+ /* entry */
{
int reg;
int sreg_count = (inst >> 6) & 3;
/* Check if the ra register was pushed on the stack. */
- reg_position = get_frame_base (fci) + PROC_REG_OFFSET (proc_desc);
+ CORE_ADDR reg_position = (get_frame_base (fci)
+ + PROC_REG_OFFSET (proc_desc));
if (inst & 0x20)
reg_position -= MIPS_SAVED_REGSIZE;
- /* Check if the s0 and s1 registers were pushed on the stack. */
+ /* Check if the s0 and s1 registers were pushed on the
+ stack. */
for (reg = 16; reg < sreg_count + 16; reg++)
{
- get_frame_saved_regs (fci)[reg] = reg_position;
+ set_reg_offset (saved_regs, reg, reg_position);
reg_position -= MIPS_SAVED_REGSIZE;
}
}
}
- /* Fill in the offsets for the registers which float_mask says
- were saved. */
- reg_position = get_frame_base (fci) + PROC_FREG_OFFSET (proc_desc);
-
- /* Apparently, the freg_offset gives the offset to the first 64 bit
- saved.
-
- When the ABI specifies 64 bit saved registers, the FREG_OFFSET
- designates the first saved 64 bit register.
-
- When the ABI specifies 32 bit saved registers, the ``64 bit saved
- DOUBLE'' consists of two adjacent 32 bit registers, Hence
- FREG_OFFSET, designates the address of the lower register of the
- register pair. Adjust the offset so that it designates the upper
- register of the pair -- i.e., the address of the first saved 32
- bit register. */
-
- if (MIPS_SAVED_REGSIZE == 4)
- reg_position += MIPS_SAVED_REGSIZE;
-
- /* Fill in the offsets for the float registers which float_mask says
- were saved. */
- for (ireg = MIPS_NUMREGS - 1; float_mask; --ireg, float_mask <<= 1)
- if (float_mask & 0x80000000)
- {
- get_frame_saved_regs (fci)[FP0_REGNUM + ireg] = reg_position;
- reg_position -= MIPS_SAVED_REGSIZE;
- }
+ /* Fill in the offsets for the registers which float_mask says were
+ saved. */
+ {
+ CORE_ADDR reg_position = (get_frame_base (fci)
+ + PROC_FREG_OFFSET (proc_desc));
- get_frame_saved_regs (fci)[PC_REGNUM] = get_frame_saved_regs (fci)[RA_REGNUM];
-}
+ /* Apparently, the freg_offset gives the offset to the first 64
+ bit saved.
-/* Set up the 'saved_regs' array. This is a data structure containing
- the addresses on the stack where each register has been saved, for
- each stack frame. Registers that have not been saved will have
- zero here. The stack pointer register is special: rather than the
- address where the stack register has been saved, saved_regs[SP_REGNUM]
- will have the actual value of the previous frame's stack register. */
+ When the ABI specifies 64 bit saved registers, the FREG_OFFSET
+ designates the first saved 64 bit register.
-static void
-mips_frame_init_saved_regs (struct frame_info *frame)
-{
- if (get_frame_saved_regs (frame) == NULL)
- {
- mips_find_saved_regs (frame);
- }
- get_frame_saved_regs (frame)[SP_REGNUM] = get_frame_base (frame);
+ When the ABI specifies 32 bit saved registers, the ``64 bit
+ saved DOUBLE'' consists of two adjacent 32 bit registers, Hence
+ FREG_OFFSET, designates the address of the lower register of
+ the register pair. Adjust the offset so that it designates the
+ upper register of the pair -- i.e., the address of the first
+ saved 32 bit register. */
+
+ if (MIPS_SAVED_REGSIZE == 4)
+ reg_position += MIPS_SAVED_REGSIZE;
+
+ /* Fill in the offsets for the float registers which float_mask
+ says were saved. */
+ for (ireg = MIPS_NUMREGS - 1; float_mask; --ireg, float_mask <<= 1)
+ if (float_mask & 0x80000000)
+ {
+ set_reg_offset (saved_regs, FP0_REGNUM + ireg, reg_position);
+ reg_position -= MIPS_SAVED_REGSIZE;
+ }
+
+ set_reg_offset (saved_regs, PC_REGNUM, saved_regs[RA_REGNUM]);
+ }
+
+ /* SP_REGNUM, contains the value and not the address. */
+ set_reg_offset (saved_regs, SP_REGNUM, get_frame_base (fci));
}
static CORE_ADDR
@@ -1782,16 +1782,16 @@
frames. */
static CORE_ADDR *temp_saved_regs;
-/* Set a register's saved stack address in temp_saved_regs. If an address
- has already been set for this register, do nothing; this way we will
- only recognize the first save of a given register in a function prologue.
- This is a helper function for mips{16,32}_heuristic_proc_desc. */
+/* Set a register's saved stack address in temp_saved_regs. If an
+ address has already been set for this register, do nothing; this
+ way we will only recognize the first save of a given register in a
+ function prologue. */
static void
-set_reg_offset (int regno, CORE_ADDR offset)
+set_reg_offset (CORE_ADDR *saved_regs, int regno, CORE_ADDR offset)
{
- if (temp_saved_regs[regno] == 0)
- temp_saved_regs[regno] = offset;
+ if (saved_regs[regno] == 0)
+ saved_regs[regno] = offset;
}
@@ -1987,26 +1987,26 @@
offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
reg = mips16_to_32_reg[(inst & 0x700) >> 8];
PROC_REG_MASK (&temp_proc_desc) |= (1 << reg);
- set_reg_offset (reg, sp + offset);
+ set_reg_offset (temp_saved_regs, reg, sp + offset);
}
else if ((inst & 0xff00) == 0xf900) /* sd reg,n($sp) */
{
offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
PROC_REG_MASK (&temp_proc_desc) |= (1 << reg);
- set_reg_offset (reg, sp + offset);
+ set_reg_offset (temp_saved_regs, reg, sp + offset);
}
else if ((inst & 0xff00) == 0x6200) /* sw $ra,n($sp) */
{
offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
PROC_REG_MASK (&temp_proc_desc) |= (1 << RA_REGNUM);
- set_reg_offset (RA_REGNUM, sp + offset);
+ set_reg_offset (temp_saved_regs, RA_REGNUM, sp + offset);
}
else if ((inst & 0xff00) == 0xfa00) /* sd $ra,n($sp) */
{
offset = mips16_get_imm (prev_inst, inst, 8, 8, 0);
PROC_REG_MASK (&temp_proc_desc) |= (1 << RA_REGNUM);
- set_reg_offset (RA_REGNUM, sp + offset);
+ set_reg_offset (temp_saved_regs, RA_REGNUM, sp + offset);
}
else if (inst == 0x673d) /* move $s1, $sp */
{
@@ -2025,14 +2025,14 @@
offset = mips16_get_imm (prev_inst, inst, 5, 4, 0);
reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, frame_addr + offset);
+ set_reg_offset (temp_saved_regs, reg, frame_addr + offset);
}
else if ((inst & 0xFF00) == 0x7900) /* sd reg,offset($s1) */
{
offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, frame_addr + offset);
+ set_reg_offset (temp_saved_regs, reg, frame_addr + offset);
}
else if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
entry_inst = inst; /* save for later processing */
@@ -2062,7 +2062,7 @@
for (reg = 4, offset = 0; reg < areg_count + 4; reg++)
{
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, sp + offset);
+ set_reg_offset (temp_saved_regs, reg, sp + offset);
offset += MIPS_SAVED_REGSIZE;
}
@@ -2071,7 +2071,7 @@
if (entry_inst & 0x20)
{
PROC_REG_MASK (&temp_proc_desc) |= 1 << RA_REGNUM;
- set_reg_offset (RA_REGNUM, sp + offset);
+ set_reg_offset (temp_saved_regs, RA_REGNUM, sp + offset);
offset -= MIPS_SAVED_REGSIZE;
}
@@ -2079,7 +2079,7 @@
for (reg = 16; reg < sreg_count + 16; reg++)
{
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, sp + offset);
+ set_reg_offset (temp_saved_regs, reg, sp + offset);
offset -= MIPS_SAVED_REGSIZE;
}
}
@@ -2124,7 +2124,7 @@
else if ((high_word & 0xFFE0) == 0xafa0) /* sw reg,offset($sp) */
{
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, sp + low_word);
+ set_reg_offset (temp_saved_regs, reg, sp + low_word);
}
else if ((high_word & 0xFFE0) == 0xffa0) /* sd reg,offset($sp) */
{
@@ -2132,7 +2132,7 @@
but the register size used is only 32 bits. Make the address
for the saved register point to the lower 32 bits. */
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, sp + low_word + 8 - MIPS_REGSIZE);
+ set_reg_offset (temp_saved_regs, reg, sp + low_word + 8 - MIPS_REGSIZE);
}
else if (high_word == 0x27be) /* addiu $30,$sp,size */
{
@@ -2182,7 +2182,7 @@
else if ((high_word & 0xFFE0) == 0xafc0) /* sw reg,offset($30) */
{
PROC_REG_MASK (&temp_proc_desc) |= 1 << reg;
- set_reg_offset (reg, frame_addr + low_word);
+ set_reg_offset (temp_saved_regs, reg, frame_addr + low_word);
}
}
}
@@ -2581,15 +2581,18 @@
if (!PC_IN_SIGTRAMP (get_frame_pc (fci), name))
{
frame_saved_regs_zalloc (fci);
- memcpy (get_frame_saved_regs (fci), temp_saved_regs, SIZEOF_FRAME_SAVED_REGS);
- get_frame_saved_regs (fci)[PC_REGNUM]
- = get_frame_saved_regs (fci)[RA_REGNUM];
- /* Set value of previous frame's stack pointer. Remember that
- saved_regs[SP_REGNUM] is special in that it contains the
- value of the stack pointer register. The other saved_regs
- values are addresses (in the inferior) at which a given
- register's value may be found. */
- get_frame_saved_regs (fci)[SP_REGNUM] = get_frame_base (fci);
+ /* Set value of previous frame's stack pointer.
+ Remember that saved_regs[SP_REGNUM] is special in
+ that it contains the value of the stack pointer
+ register. The other saved_regs values are addresses
+ (in the inferior) at which a given register's value
+ may be found. */
+ set_reg_offset (temp_saved_regs, SP_REGNUM,
+ get_frame_base (fci));
+ set_reg_offset (temp_saved_regs, PC_REGNUM,
+ temp_saved_regs[RA_REGNUM]);
+ memcpy (get_frame_saved_regs (fci), temp_saved_regs,
+ SIZEOF_FRAME_SAVED_REGS);
}
}
@@ -3807,8 +3810,7 @@
proc_desc = get_frame_extra_info (frame)->proc_desc;
write_register (PC_REGNUM, DEPRECATED_FRAME_SAVED_PC (frame));
- if (get_frame_saved_regs (frame) == NULL)
- DEPRECATED_FRAME_INIT_SAVED_REGS (frame);
+ mips_find_saved_regs (frame);
for (regnum = 0; regnum < NUM_REGS; regnum++)
if (regnum != SP_REGNUM && regnum != PC_REGNUM
&& get_frame_saved_regs (frame)[regnum])
@@ -5922,7 +5924,7 @@
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, mips_dwarf_dwarf2_ecoff_reg_to_regnum);
/* Initialize a frame */
- set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, mips_frame_init_saved_regs);
+ set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, mips_find_saved_regs);
set_gdbarch_deprecated_init_extra_frame_info (gdbarch, mips_init_extra_frame_info);
/* MIPS version of CALL_DUMMY */