[AArch64] Fix pattern guard relaxations that are allowing more constants than they should.

Submitted by Tamar Christina on Aug. 11, 2017, 11:01 a.m.

Details

Message ID 20170811110137.GA13171@arm.com
State New
Headers show

Commit Message

Tamar Christina Aug. 11, 2017, 11:01 a.m.
Hi All, 


Hi previous float immediate patches changed

aarch64_reg_or_fp_zero into aarch64_reg_or_fp_float
for each of the movdf/sf/hf causing the RTL to contain
stores to memory it would never be able to find a matching
pattern for. Reload would then decide to store them to a
register instead.

This didn't cause any incorrect code or failing tests but did change
scheduling does producing more inefficient code.

The predicate is not reverted.


Regression tested on aarch64-none-linux-gnu and no regressions.

OK for trunk?

Thanks,
Tamar


gcc/
2017-08-11  Tamar Christina  <tamar.christina@arm.com>
	* config/aarch64/aarch64.md (mov<mode>): Change.
	(*movhf_aarch64, *movsf_aarch64, *movdf_aarch64):
	aarch64_reg_or_fp_float into aarch64_reg_or_fp_zero.
	* config/aarch64/predicates.md (aarch64_reg_or_fp_float): Removed.

--

Comments

James Greenhalgh Aug. 11, 2017, 1:07 p.m.
On Fri, Aug 11, 2017 at 12:01:40PM +0100, Tamar Christina wrote:
> Hi All, 
> 
> 
> Hi previous float immediate patches changed
> 
> aarch64_reg_or_fp_zero into aarch64_reg_or_fp_float
> for each of the movdf/sf/hf causing the RTL to contain
> stores to memory it would never be able to find a matching
> pattern for. Reload would then decide to store them to a
> register instead.
> 
> This didn't cause any incorrect code or failing tests but did change
> scheduling does producing more inefficient code.
> 
> The predicate is not reverted.
>
> Regression tested on aarch64-none-linux-gnu and no regressions.
> 
> OK for trunk?

OK.

Thanks,
James

> 
> Thanks,
> Tamar
> 
> 
> gcc/
> 2017-08-11  Tamar Christina  <tamar.christina@arm.com>
> 	* config/aarch64/aarch64.md (mov<mode>): Change.
> 	(*movhf_aarch64, *movsf_aarch64, *movdf_aarch64):
> 	aarch64_reg_or_fp_float into aarch64_reg_or_fp_zero.
> 	* config/aarch64/predicates.md (aarch64_reg_or_fp_float): Removed.
> 
> --

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diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 7609fdba22627f15ed7630c371587b14b72e02ec..ba9c4479605fc6e001822a0f0e1df7d61ab58e0f 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -1076,7 +1076,7 @@ 
   [(set (match_operand:HF 0 "nonimmediate_operand" "=w,w  ,?r,w,w  ,w  ,w,m,r,m ,r")
 	(match_operand:HF 1 "general_operand"      "Y ,?rY, w,w,Ufc,Uvi,m,w,m,rY,r"))]
   "TARGET_FLOAT && (register_operand (operands[0], HFmode)
-    || aarch64_reg_or_fp_float (operands[1], HFmode))"
+    || aarch64_reg_or_fp_zero (operands[1], HFmode))"
   "@
    movi\\t%0.4h, #0
    fmov\\t%h0, %w1
@@ -1099,7 +1099,7 @@ 
   [(set (match_operand:SF 0 "nonimmediate_operand" "=w,w  ,?r,w,w  ,w  ,w,m,r,m ,r,r")
 	(match_operand:SF 1 "general_operand"      "Y ,?rY, w,w,Ufc,Uvi,m,w,m,rY,r,M"))]
   "TARGET_FLOAT && (register_operand (operands[0], SFmode)
-    || aarch64_reg_or_fp_float (operands[1], SFmode))"
+    || aarch64_reg_or_fp_zero (operands[1], SFmode))"
   "@
    movi\\t%0.2s, #0
    fmov\\t%s0, %w1
@@ -1123,7 +1123,7 @@ 
   [(set (match_operand:DF 0 "nonimmediate_operand" "=w, w  ,?r,w,w  ,w  ,w,m,r,m ,r,r")
 	(match_operand:DF 1 "general_operand"      "Y , ?rY, w,w,Ufc,Uvi,m,w,m,rY,r,N"))]
   "TARGET_FLOAT && (register_operand (operands[0], DFmode)
-    || aarch64_reg_or_fp_float (operands[1], DFmode))"
+    || aarch64_reg_or_fp_zero (operands[1], DFmode))"
   "@
    movi\\t%d0, #0
    fmov\\t%d0, %x1
diff --git a/gcc/config/aarch64/predicates.md b/gcc/config/aarch64/predicates.md
index 95d28cfa33c6e06c47b6c666af6d8c2d6cef20f4..11243c4ce00aa7d16a886bb24b01180801c68f4e 100644
--- a/gcc/config/aarch64/predicates.md
+++ b/gcc/config/aarch64/predicates.md
@@ -57,11 +57,6 @@ 
        (ior (match_operand 0 "register_operand")
 	    (match_test "op == const0_rtx"))))
 
-(define_predicate "aarch64_reg_or_fp_float"
-  (ior (match_operand 0 "register_operand")
-	(and (match_code "const_double")
-	     (match_test "aarch64_float_const_rtx_p (op)"))))
-
 (define_predicate "aarch64_reg_or_fp_zero"
   (ior (match_operand 0 "register_operand")
 	(and (match_code "const_double")