-----Original Message-----
From: Richard Earnshaw
Sent: 17 October 2012 11:14
To: Greta Yorsh
Cc: GCC Patches; Ramana Radhakrishnan; ni...@redhat.com;
p...@codesourcery.com
Subject: Re: [PING][Patch, ARM] cleanup prologue_use pattern
On 17/10/12 11:08, Greta Yorsh wrote:
Ping!
I've been pondering why this was being asked for. As far as I can tell
it's just a naming issue (mention of the epilogue in the prologue).
The right thing to do is to rename the pattern to reflect the dual use
rather than add additional patterns with identical NOP behaviour. Can't
you just rename the existing pattern? Something like "force_register_use"?
R.
Thanks,
Greta
-----Original Message-----
From: Greta Yorsh [mailto:greta.yo...@arm.com]
Sent: 10 October 2012 16:14
To: GCC Patches
Cc: Ramana Radhakrishnan; Richard Earnshaw; ni...@redhat.com;
p...@codesourcery.com
Subject: [Patch, ARM] cleanup prologue_use pattern
The pattern prologue_use is emitted for both prologue and epilogue.
In particular, the assembly comment
"@sp needed for prologue"
is printed out for both prologue and epilogue.
This patch adds a separate pattern for epilogue_use and replaces
prologue_use with epilogue_use where appropriate.
No regression on qemu for arm-none-eabi.
Ok for trunk?
Thanks,
Greta
2012-09-17 Greta Yorsh <greta.yo...@arm.com>
* config/arm/arm.md (UNSPEC_EPILOGUE_USE): New unspec value.
(sibcall_epilogue): Use UNSPEC_EPILOGUE_USE instead of
UNSPEC_PROLOGUE_USE.
(epilogue_use): New define_insn.
(epilogue): Use gen_epilogue_use instead of gen_prologue_use.
* config/arm/arm.c (arm_expand_epilogue): Likewise.
(thumb1_expand_epilogue) Likewise.
rename-prolog-use.v2.patch.txt
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index dd073da..f23c2d0 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -22581,7 +22581,7 @@ thumb1_expand_epilogue (void)
/* Emit a USE (stack_pointer_rtx), so that
the stack adjustment will not be deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_epilogue_use (stack_pointer_rtx));
if (crtl->profile || !TARGET_SCHED_PROLOG)
emit_insn (gen_blockage ());
@@ -22805,7 +22805,7 @@ arm_expand_epilogue (bool really_return)
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment
is not
deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_epilogue_use (stack_pointer_rtx));
}
else
{
@@ -22823,7 +22823,7 @@ arm_expand_epilogue (bool really_return)
emit_insn (gen_movsi (stack_pointer_rtx,
hard_frame_pointer_rtx));
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment
is not
deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_epilogue_use (stack_pointer_rtx));
}
}
else
@@ -22841,7 +22841,7 @@ arm_expand_epilogue (bool really_return)
GEN_INT (amount)));
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment
is
not deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_epilogue_use (stack_pointer_rtx));
}
}
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index a60e659..6a910a3 100644
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -81,6 +81,7 @@
; instructions setting registers for EH handling
; and stack frame generation. Operand 0 is the
; register to "use".
+ UNSPEC_EPILOGUE_USE ; Same for epilogue.
UNSPEC_CHECK_ARCH ; Set CCs to indicate 26-bit or 32-bit mode.
UNSPEC_WSHUFH ; Used by the intrinsic form of the iWMMXt
WSHUFH instruction.
UNSPEC_WACC ; Used by the intrinsic form of the iWMMXt WACC
instruction.
@@ -10610,7 +10611,7 @@
"TARGET_EITHER"
"
if (crtl->calls_eh_return)
- emit_insn (gen_prologue_use (gen_rtx_REG (Pmode, 2)));
+ emit_insn (gen_epilogue_use (gen_rtx_REG (Pmode, 2)));
if (TARGET_THUMB1)
{
thumb1_expand_epilogue ();
@@ -10644,7 +10645,7 @@
;; does not think that it is unused by the sibcall branch that
;; will replace the standard function epilogue.
(define_expand "sibcall_epilogue"
- [(parallel [(unspec:SI [(reg:SI LR_REGNUM)] UNSPEC_PROLOGUE_USE)
+ [(parallel [(unspec:SI [(reg:SI LR_REGNUM)] UNSPEC_EPILOGUE_USE)
(unspec_volatile [(return)] VUNSPEC_EPILOGUE)])]
"TARGET_32BIT"
"
@@ -11267,6 +11268,12 @@
[(set_attr "length" "0")]
)
+(define_insn "epilogue_use"
+ [(unspec:SI [(match_operand:SI 0 "register_operand" "")]
UNSPEC_EPILOGUE_USE)]
+ ""
+ "%@ %0 needed for epilogue"
+ [(set_attr "length" "0")]
+)
;; Patterns for exception handling
rename_prologue_use.v3.patch.txt
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 11f0037..248ed09 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -16671,7 +16671,7 @@ arm_expand_prologue (void)
}
emit_set_insn (ip_rtx, insn);
/* Add a USE to stop propagate_one_insn() from barfing. */
- emit_insn (gen_prologue_use (ip_rtx));
+ emit_insn (gen_force_register_use (ip_rtx));
}
}
else
@@ -22581,7 +22581,7 @@ thumb1_expand_epilogue (void)
/* Emit a USE (stack_pointer_rtx), so that
the stack adjustment will not be deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_force_register_use (stack_pointer_rtx));
if (crtl->profile || !TARGET_SCHED_PROLOG)
emit_insn (gen_blockage ());
@@ -22805,7 +22805,7 @@ arm_expand_epilogue (bool really_return)
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment is
not
deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_force_register_use (stack_pointer_rtx));
}
else
{
@@ -22823,7 +22823,7 @@ arm_expand_epilogue (bool really_return)
emit_insn (gen_movsi (stack_pointer_rtx, hard_frame_pointer_rtx));
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment is
not
deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_force_register_use (stack_pointer_rtx));
}
}
else
@@ -22841,7 +22841,7 @@ arm_expand_epilogue (bool really_return)
GEN_INT (amount)));
/* Emit USE(stack_pointer_rtx) to ensure that stack adjustment is
not deleted. */
- emit_insn (gen_prologue_use (stack_pointer_rtx));
+ emit_insn (gen_force_register_use (stack_pointer_rtx));
}
}
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index 4735ad2..6cc4e81 100644
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -76,7 +76,7 @@
; that points at the containing instruction.
UNSPEC_PRLG_STK ; A special barrier that prevents frame accesses
; being scheduled before the stack adjustment insn.
- UNSPEC_PROLOGUE_USE ; As USE insns are not meaningful after reload,
+ UNSPEC_REGISTER_USE ; As USE insns are not meaningful after reload,
; this unspec is used to prevent the deletion of
; instructions setting registers for EH handling
; and stack frame generation. Operand 0 is the
@@ -10748,7 +10748,7 @@
"TARGET_EITHER"
"
if (crtl->calls_eh_return)
- emit_insn (gen_prologue_use (gen_rtx_REG (Pmode, 2)));
+ emit_insn (gen_force_register_use (gen_rtx_REG (Pmode, 2)));
if (TARGET_THUMB1)
{
thumb1_expand_epilogue ();
@@ -10782,7 +10782,7 @@
;; does not think that it is unused by the sibcall branch that
;; will replace the standard function epilogue.
(define_expand "sibcall_epilogue"
- [(parallel [(unspec:SI [(reg:SI LR_REGNUM)] UNSPEC_PROLOGUE_USE)
+ [(parallel [(unspec:SI [(reg:SI LR_REGNUM)] UNSPEC_REGISTER_USE)
(unspec_volatile [(return)] VUNSPEC_EPILOGUE)])]
"TARGET_32BIT"
"
@@ -11398,10 +11398,10 @@
""
)
-(define_insn "prologue_use"
- [(unspec:SI [(match_operand:SI 0 "register_operand" "")]
UNSPEC_PROLOGUE_USE)]
+(define_insn "force_register_use"
+ [(unspec:SI [(match_operand:SI 0 "register_operand" "")]
UNSPEC_REGISTER_USE)]
""
- "%@ %0 needed for prologue"
+ "%@ %0 needed"
[(set_attr "length" "0")]
)
