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(last_setjmp_suid, regs_crosses_setjmp): New variables.

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(stupid_life_analysis, stupid_mark_refs): Use them to track which
regs are live over a setjmp; don't allocate such regs.

From-SVN: r11573
This commit is contained in:
Richard Kenner 1996-03-20 08:04:28 -05:00
parent ba9d9bfa1c
commit 68f0213570
1 changed files with 23 additions and 2 deletions
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25
gcc/stupid.c
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@ -65,6 +65,11 @@ static int *uid_suid;
static int last_call_suid;
/* Record the suid of the last NOTE_INSN_SETJMP
so we can tell whether a pseudo reg crosses any setjmp. */
static int last_setjmp_suid;
/* Element N is suid of insn where life span of pseudo reg N ends.
Element is 0 if register N has not been seen yet on backward scan. */
@ -88,6 +93,10 @@ static char *regs_live;
static char *regs_change_size;
/* Indexed by reg number, nonzero if reg crosses a setjmp. */
static char *regs_crosses_setjmp;
/* Indexed by insn's suid, the set of hard regs live after that insn. */
static HARD_REG_SET *after_insn_hard_regs;
@ -148,6 +157,7 @@ stupid_life_analysis (f, nregs, file)
}
last_call_suid = i + 1;
last_setjmp_suid = i + 1;
max_suid = i + 1;
max_regno = nregs;
@ -166,6 +176,9 @@ stupid_life_analysis (f, nregs, file)
regs_change_size = (char *) alloca (nregs * sizeof (char));
bzero ((char *) regs_change_size, nregs * sizeof (char));
regs_crosses_setjmp = (char *) alloca (nregs * sizeof (char));
bzero ((char *) regs_crosses_setjmp, nregs * sizeof (char));
reg_renumber = (short *) oballoc (nregs * sizeof (short));
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
reg_renumber[i] = i;
@ -215,6 +228,10 @@ stupid_life_analysis (f, nregs, file)
if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
stupid_mark_refs (PATTERN (insn), insn);
if (GET_CODE (insn) == NOTE
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP)
last_setjmp_suid = INSN_SUID (insn);
/* Mark all call-clobbered regs as live after each call insn
so that a pseudo whose life span includes this insn
will not go in one of them.
@ -253,8 +270,9 @@ stupid_life_analysis (f, nregs, file)
{
register int r = reg_order[i];
/* Some regnos disappear from the rtl. Ignore them to avoid crash. */
if (regno_reg_rtx[r] == 0)
/* Some regnos disappear from the rtl. Ignore them to avoid crash.
Also don't allocate registers that cross a setjmp. */
if (regno_reg_rtx[r] == 0 || regs_crosses_setjmp[r])
continue;
/* Now find the best hard-register class for this pseudo register */
@ -494,6 +512,9 @@ stupid_mark_refs (x, insn)
if (last_call_suid < reg_where_dead[regno])
reg_n_calls_crossed[regno] += 1;
if (last_setjmp_suid < reg_where_dead[regno])
regs_crosses_setjmp[regno] = 1;
}
}