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-rw-r--r--gcc/ChangeLog12
-rw-r--r--gcc/basic-block.h2
-rw-r--r--gcc/final.c6
-rw-r--r--gcc/flow.c39
-rw-r--r--gcc/global.c40
-rw-r--r--gcc/regs.h7
6 files changed, 87 insertions, 19 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6ce8f999b23..0cf45b6c3ec 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2003-12-06 Alan Modra <amodra@bigpond.net.au>
+
+ PR 13169
+ * basic-block.h (PROP_ASM_SCAN): Define.
+ * final.c (regs_asm_clobbered): New array.
+ * regs.h (regs_asm_clobbered): Declare.
+ * flow.c (life_analysis): Init it.
+ (mark_set_regs): Set PROP_ASM_SCAN for asms.
+ (mark_set_1): Set regs_asm_clobbered.
+ * global.c (global_alloc): Don't set eliminable_regset when
+ regs_asm_clobbered.
+
2003-12-05 Mark Mitchell <mark@codesourcery.com>
* config/ia64/ia64.h (MUST_PASS_IN_STACK): Define.
diff --git a/gcc/basic-block.h b/gcc/basic-block.h
index 221b2466985..365711a541d 100644
--- a/gcc/basic-block.h
+++ b/gcc/basic-block.h
@@ -477,6 +477,8 @@ enum update_life_extent
#define PROP_AUTOINC 64 /* Create autoinc mem references. */
#define PROP_EQUAL_NOTES 128 /* Take into account REG_EQUAL notes. */
#define PROP_SCAN_DEAD_STORES 256 /* Scan for dead code. */
+#define PROP_ASM_SCAN 512 /* Internal flag used within flow.c
+ to flag analysis of asms. */
#define PROP_FINAL (PROP_DEATH_NOTES | PROP_LOG_LINKS \
| PROP_REG_INFO | PROP_KILL_DEAD_CODE \
| PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
diff --git a/gcc/final.c b/gcc/final.c
index 820cb680ab2..53c9359232c 100644
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -170,6 +170,12 @@ CC_STATUS cc_prev_status;
char regs_ever_live[FIRST_PSEUDO_REGISTER];
+/* Like regs_ever_live, but 1 if a reg is set or clobbered from an asm.
+ Unlike regs_ever_live, elements of this array corresponding to
+ eliminable regs like the frame pointer are set if an asm sets them. */
+
+char regs_asm_clobbered[FIRST_PSEUDO_REGISTER];
+
/* Nonzero means current function must be given a frame pointer.
Initialized in function.c to 0. Set only in reload1.c as per
the needs of the function. */
diff --git a/gcc/flow.c b/gcc/flow.c
index d131fab5a8b..952e7d9eb92 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -464,7 +464,10 @@ life_analysis (rtx f, FILE *file, int flags)
is not immediately handy. */
if (flags & PROP_REG_INFO)
- memset (regs_ever_live, 0, sizeof (regs_ever_live));
+ {
+ memset (regs_ever_live, 0, sizeof (regs_ever_live));
+ memset (regs_asm_clobbered, 0, sizeof (regs_asm_clobbered));
+ }
update_life_info (NULL, UPDATE_LIFE_GLOBAL, flags);
/* Clean up. */
@@ -2445,6 +2448,7 @@ mark_set_regs (struct propagate_block_info *pbi, rtx x, rtx insn)
rtx cond = NULL_RTX;
rtx link;
enum rtx_code code;
+ int flags = pbi->flags;
if (insn)
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
@@ -2453,14 +2457,17 @@ mark_set_regs (struct propagate_block_info *pbi, rtx x, rtx insn)
mark_set_1 (pbi, SET, XEXP (link, 0),
(GET_CODE (x) == COND_EXEC
? COND_EXEC_TEST (x) : NULL_RTX),
- insn, pbi->flags);
+ insn, flags);
}
retry:
switch (code = GET_CODE (x))
{
case SET:
+ if (GET_CODE (XEXP (x, 1)) == ASM_OPERANDS)
+ flags |= PROP_ASM_SCAN;
+ /* Fall thru */
case CLOBBER:
- mark_set_1 (pbi, code, SET_DEST (x), cond, insn, pbi->flags);
+ mark_set_1 (pbi, code, SET_DEST (x), cond, insn, flags);
return;
case COND_EXEC:
@@ -2483,13 +2490,20 @@ mark_set_regs (struct propagate_block_info *pbi, rtx x, rtx insn)
cond = COND_EXEC_TEST (sub);
sub = COND_EXEC_CODE (sub);
- if (GET_CODE (sub) != SET && GET_CODE (sub) != CLOBBER)
- break;
- /* Fall through. */
+ if (GET_CODE (sub) == SET)
+ goto mark_set;
+ if (GET_CODE (sub) == CLOBBER)
+ goto mark_clob;
+ break;
case SET:
+ mark_set:
+ if (GET_CODE (XEXP (sub, 1)) == ASM_OPERANDS)
+ flags |= PROP_ASM_SCAN;
+ /* Fall thru */
case CLOBBER:
- mark_set_1 (pbi, code, SET_DEST (sub), cond, insn, pbi->flags);
+ mark_clob:
+ mark_set_1 (pbi, code, SET_DEST (sub), cond, insn, flags);
break;
default:
@@ -2713,6 +2727,9 @@ mark_set_1 (struct propagate_block_info *pbi, enum rtx_code code, rtx reg, rtx c
{
for (i = regno_first; i <= regno_last; i++)
regs_ever_live[i] = 1;
+ if (flags & PROP_ASM_SCAN)
+ for (i = regno_first; i <= regno_last; i++)
+ regs_asm_clobbered[i] = 1;
}
else
{
@@ -2798,6 +2815,14 @@ mark_set_1 (struct propagate_block_info *pbi, enum rtx_code code, rtx reg, rtx c
{
if (flags & (PROP_LOG_LINKS | PROP_AUTOINC))
pbi->reg_next_use[regno_first] = 0;
+
+ if ((flags & PROP_REG_INFO) != 0
+ && (flags & PROP_ASM_SCAN) != 0
+ && regno_first < FIRST_PSEUDO_REGISTER)
+ {
+ for (i = regno_first; i <= regno_last; i++)
+ regs_asm_clobbered[i] = 1;
+ }
}
/* If this is the last pass and this is a SCRATCH, show it will be dying
diff --git a/gcc/global.c b/gcc/global.c
index c808e207406..c337cd41cfc 100644
--- a/gcc/global.c
+++ b/gcc/global.c
@@ -343,22 +343,42 @@ global_alloc (FILE *file)
#ifdef ELIMINABLE_REGS
for (i = 0; i < ARRAY_SIZE (eliminables); i++)
{
- SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from);
+ bool cannot_elim
+ = (! CAN_ELIMINATE (eliminables[i].from, eliminables[i].to)
+ || (eliminables[i].to == STACK_POINTER_REGNUM && need_fp));
- if (! CAN_ELIMINATE (eliminables[i].from, eliminables[i].to)
- || (eliminables[i].to == STACK_POINTER_REGNUM && need_fp))
- SET_HARD_REG_BIT (no_global_alloc_regs, eliminables[i].from);
+ if (!regs_asm_clobbered[eliminables[i].from])
+ {
+ SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from);
+
+ if (cannot_elim)
+ SET_HARD_REG_BIT (no_global_alloc_regs, eliminables[i].from);
+ }
+ else if (cannot_elim)
+ error ("%s cannot be used in asm here",
+ reg_names[eliminables[i].from]);
}
#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
- SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM);
- if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, HARD_FRAME_POINTER_REGNUM);
+ if (!regs_asm_clobbered[HARD_FRAME_POINTER_REGNUM])
+ {
+ SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM);
+ if (need_fp)
+ SET_HARD_REG_BIT (no_global_alloc_regs, HARD_FRAME_POINTER_REGNUM);
+ }
+ else if (need_fp)
+ error ("%s cannot be used in asm here",
+ reg_names[HARD_FRAME_POINTER_REGNUM]);
#endif
#else
- SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM);
- if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, FRAME_POINTER_REGNUM);
+ if (!regs_asm_clobbered[FRAME_POINTER_REGNUM])
+ {
+ SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM);
+ if (need_fp)
+ SET_HARD_REG_BIT (no_global_alloc_regs, FRAME_POINTER_REGNUM);
+ }
+ else if (need_fp)
+ error ("%s cannot be used in asm here", reg_names[FRAME_POINTER_REGNUM]);
#endif
/* Track which registers have already been used. Start with registers
diff --git a/gcc/regs.h b/gcc/regs.h
index b2aeb5fb02c..9c9edccb26b 100644
--- a/gcc/regs.h
+++ b/gcc/regs.h
@@ -153,11 +153,14 @@ extern bitmap_head subregs_of_mode;
extern short *reg_renumber;
-/* Vector indexed by hardware reg
- saying whether that reg is ever used. */
+/* Vector indexed by hardware reg saying whether that reg is ever used. */
extern char regs_ever_live[FIRST_PSEUDO_REGISTER];
+/* Like regs_ever_live, but saying whether reg is set by asm statements. */
+
+extern char regs_asm_clobbered[FIRST_PSEUDO_REGISTER];
+
/* For each hard register, the widest mode object that it can contain.
This will be a MODE_INT mode if the register can hold integers. Otherwise
it will be a MODE_FLOAT or a MODE_CC mode, whichever is valid for the