As noted in fixed_reg_p comment
/* Return whether REG is a global user reg or has been specifed by
-ffixed-REG. We should not restore these, and so cannot use
lmw or out-of-line restore functions if there are any. We also
can't save them (well, emit frame notes for them), because frame
unwinding during exception handling will restore saved registers. */
* config/rs6000/rs6000.c (rs6000_savres_strategy): Don't restore
fixed regs.
Bootstrapped and regression tested powerpc64-linux (-m32 too) and
powerpc64le-linux. OK?
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 74158cd..b628808 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -24309,6 +24309,7 @@ rs6000_savres_strategy (rs6000_stack_t *info,
bool using_static_chain_p)
{
int strategy = 0;
+ int i;
/* Select between in-line and out-of-line save and restore of regs.
First, all the obvious cases where we don't use out-of-line. */
@@ -24383,6 +24384,17 @@ rs6000_savres_strategy (rs6000_stack_t *info,
| SAVE_INLINE_GPRS
| SAVE_INLINE_VRS);
+ /* Don't ever restore fixed regs. That means we can't use the
+ out-of-line register restore functions if a fixed reg is in the
+ range of regs restored. */
+ if (!(strategy & REST_INLINE_FPRS))
+ for (i = info->first_fp_reg_save; i < 64; i++)
+ if (fixed_regs[i])
+ {
+ strategy |= REST_INLINE_FPRS;
+ break;
+ }
+
/* We can only use the out-of-line routines to restore fprs if we've
saved all the registers from first_fp_reg_save in the prologue.
Otherwise, we risk loading garbage. Of course, if we have saved
@@ -24390,10 +24402,8 @@ rs6000_savres_strategy (rs6000_stack_t *info,
if ((strategy & SAVE_INLINE_FPRS)
&& !(strategy & REST_INLINE_FPRS))
{
- int i;
-
for (i = info->first_fp_reg_save; i < 64; i++)
- if (fixed_regs[i] || !save_reg_p (i))
+ if (!save_reg_p (i))
{
strategy |= REST_INLINE_FPRS;
break;
@@ -24401,13 +24411,19 @@ rs6000_savres_strategy (rs6000_stack_t *info,
}
/* Similarly, for altivec regs. */
+ if (!(strategy & REST_INLINE_VRS))
+ for (i = info->first_altivec_reg_save; i < LAST_ALTIVEC_REGNO + 1; i++)
+ if (fixed_regs[i])
+ {
+ strategy |= REST_INLINE_VRS;
+ break;
+ }
+
if ((strategy & SAVE_INLINE_VRS)
&& !(strategy & REST_INLINE_VRS))
{
- int i;
-
for (i = info->first_altivec_reg_save; i < LAST_ALTIVEC_REGNO + 1; i++)
- if (fixed_regs[i] || !save_reg_p (i))
+ if (!save_reg_p (i))
{
strategy |= REST_INLINE_VRS;
break;
@@ -24467,6 +24483,16 @@ rs6000_savres_strategy (rs6000_stack_t *info,
}
}
+ /* Don't ever restore fixed regs. */
+ if ((strategy & (REST_INLINE_GPRS | REST_MULTIPLE)) != REST_INLINE_GPRS)
+ for (i = info->first_gp_reg_save; i < 32; i++)
+ if (fixed_reg_p (i))
+ {
+ strategy |= REST_INLINE_GPRS;
+ strategy &= ~REST_MULTIPLE;
+ break;
+ }
+
/* We can only use load multiple or the out-of-line routines to
restore gprs if we've saved all the registers from
first_gp_reg_save. Otherwise, we risk loading garbage.
@@ -24475,10 +24501,8 @@ rs6000_savres_strategy (rs6000_stack_t *info,
if ((strategy & (SAVE_INLINE_GPRS | SAVE_MULTIPLE)) == SAVE_INLINE_GPRS
&& (strategy & (REST_INLINE_GPRS | REST_MULTIPLE)) != REST_INLINE_GPRS)
{
- int i;
-
for (i = info->first_gp_reg_save; i < 32; i++)
- if (fixed_reg_p (i) || !save_reg_p (i))
+ if (!save_reg_p (i))
{
strategy |= REST_INLINE_GPRS;
strategy &= ~REST_MULTIPLE;
--
Alan Modra
Australia Development Lab, IBM
