===================================================================
@@ -26083,10 +26083,14 @@ rs6000_emit_savres_rtx (rs6000_stack_t *
return insn;
}
-/* Emit code to store CR fields that need to be saved into REG. */
+/* Emit prolog code to store CR fields that need to be saved into REG. This
+ function should only be called when moving the non-volatile CRs to REG, it
+ is not a general purpose routine to move the entire set of CRs to REG.
+ Specifically, gen_prolog_movesi_from_cr() does not contain uses of the
+ volatile CRs. */
static void
-rs6000_emit_move_from_cr (rtx reg)
+rs6000_emit_prolog_move_from_cr (rtx reg)
{
/* Only the ELFv2 ABI allows storing only selected fields. */
if (DEFAULT_ABI == ABI_ELFv2 && TARGET_MFCRF)
@@ -26117,7 +26121,7 @@ rs6000_emit_move_from_cr (rtx reg)
as well, using logical operations to combine the values. */
}
- emit_insn (gen_movesi_from_cr (reg));
+ emit_insn (gen_prolog_movesi_from_cr (reg));
}
/* Return whether the split-stack arg pointer (r12) is used. */
@@ -26857,7 +26861,7 @@ rs6000_emit_prologue (void)
{
cr_save_rtx = gen_rtx_REG (SImode, cr_save_regno);
START_USE (cr_save_regno);
- rs6000_emit_move_from_cr (cr_save_rtx);
+ rs6000_emit_prolog_move_from_cr (cr_save_rtx);
}
/* Do any required saving of fpr's. If only one or two to save, do
@@ -27095,7 +27099,7 @@ rs6000_emit_prologue (void)
{
START_USE (0);
cr_save_rtx = gen_rtx_REG (SImode, 0);
- rs6000_emit_move_from_cr (cr_save_rtx);
+ rs6000_emit_prolog_move_from_cr (cr_save_rtx);
}
/* Saving CR requires a two-instruction sequence: one instruction
@@ -27182,7 +27186,7 @@ rs6000_emit_prologue (void)
/* ??? We might get better performance by using multiple mfocrf
instructions. */
crsave = gen_rtx_REG (SImode, 0);
- emit_insn (gen_movesi_from_cr (crsave));
+ emit_insn (gen_prolog_movesi_from_cr (crsave));
for (i = 0; i < 8; i++)
if (!call_used_regs[CR0_REGNO + i])
===================================================================
@@ -13032,12 +13032,14 @@ (define_insn "*movesi_from_cr_one"
}"
[(set_attr "type" "mfcrf")])
-(define_insn "movesi_from_cr"
+;; Don't include the volatile CRs since their values are not used wrt CR save
+;; in the prolog and doing so prevents shrink-wrapping because we can't move the
+;; prolog past an insn (early exit test) that defines a register used in the
+;; prolog.
+(define_insn "prolog_movesi_from_cr"
[(set (match_operand:SI 0 "gpc_reg_operand" "=r")
- (unspec:SI [(reg:CC CR0_REGNO) (reg:CC CR1_REGNO)
- (reg:CC CR2_REGNO) (reg:CC CR3_REGNO)
- (reg:CC CR4_REGNO) (reg:CC CR5_REGNO)
- (reg:CC CR6_REGNO) (reg:CC CR7_REGNO)]
+ (unspec:SI [(reg:CC CR2_REGNO) (reg:CC CR3_REGNO)
+ (reg:CC CR4_REGNO)]
UNSPEC_MOVESI_FROM_CR))]
""
"mfcr %0"
===================================================================
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-rtl-pro_and_epilogue" } */
+
+void foo(int i)
+{
+ if (i > 0)
+ /* Non-volatile CR kill on true path should not prevent shrink-wrap. */
+ asm ("" : : : "cr2", "cr3");
+}
+
+/* { dg-final { scan-rtl-dump-times "Performing shrink-wrapping" 1 "pro_and_epilogue" } } */