On 19/10/15 15:37, Kyrill Tkachov wrote:
Hi Bernd,
On 19/10/15 15:31, Bernd Schmidt wrote:
On 10/19/2015 03:57 PM, Kyrill Tkachov wrote:
This second patch teaches simplify_binary_operation to return the
dereferenced
constants from the constant pool in the binary expression if other
simplifications failed.
This, combined with the 1/2 patch for aarch64
(https://gcc.gnu.org/ml/gcc-patches/2015-10/msg01744.html) allow for:
int
foo (float a)
{
return a * 32.0f;
}
to generate the code:
foo:
fcvtzs w0, s0, #5
ret
because combine now successfully tries to match:
(set (reg/i:SI 0 x0)
(fix:SI (mult:SF (reg:SF 32 v0 [ a ])
(const_double:SF 3.2e+1 [0x0.8p+6]))))
whereas before it would not try the to use the const_double directly
but rather its constant pool reference.
The only way I could see a problem with that if there are circumstances where
the memory variant would simplify further. That doesn't seem highly likely,
so...
I that were the case, I'd expect the earlier call to
simplify_binary_operation_1 have returned a non-NULL rtx,
and the code in this patch would not come into play.
* simplify-rtx.c (simplify_binary_operation): If either operand was
a constant pool reference use them if all other simplifications
failed.
Ok.
Thanks,
I'll commit it when the first (aarch64-specific) patch is approved.
This patch has already been ok'd, but I'd like to update the aarch64 test to
use scan-assembler-times
rather that just scan-assembler in light of Marcus' feedback to another patch.
I committed this version to trunk with r229086.
Thanks,
Kyrill
2015-10-20 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
* simplify-rtx.c (simplify_binary_operation): If either operand was
a constant pool reference use them if all other simplifications failed.
2015-10-20 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
* gcc.target/aarch64/fmul_fcvt_1.c: Add multiply-by-32 cases.
Kyrill
Bernd
Index: gcc/testsuite/gcc.target/aarch64/fmul_fcvt_1.c
===================================================================
--- gcc/testsuite/gcc.target/aarch64/fmul_fcvt_1.c (revision 229085)
+++ gcc/testsuite/gcc.target/aarch64/fmul_fcvt_1.c (working copy)
@@ -83,6 +83,16 @@
/* { dg-final { scan-assembler-times "fcvtzu\tx\[0-9\], d\[0-9\]*.*#4" 1 } } */
/* { dg-final { scan-assembler-times "fcvtzu\tw\[0-9\], d\[0-9\]*.*#4" 1 } } */
+FUNC_DEFS (32)
+FUNC_DEFD (32)
+/* { dg-final { scan-assembler-times "fcvtzs\tw\[0-9\], s\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzs\tx\[0-9\], s\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzs\tx\[0-9\], d\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzs\tw\[0-9\], d\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzu\tw\[0-9\], s\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzu\tx\[0-9\], s\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzu\tx\[0-9\], d\[0-9\]*.*#5" 1 } } */
+/* { dg-final { scan-assembler-times "fcvtzu\tw\[0-9\], d\[0-9\]*.*#5" 1 } } */
#define FUNC_TESTS(__a, __b) \
do \
@@ -120,10 +130,12 @@
FUNC_TESTS (4, i);
FUNC_TESTS (8, i);
FUNC_TESTS (16, i);
+ FUNC_TESTS (32, i);
FUNC_TESTD (4, i);
FUNC_TESTD (8, i);
FUNC_TESTD (16, i);
+ FUNC_TESTD (32, i);
}
return 0;
}
Index: gcc/simplify-rtx.c
===================================================================
--- gcc/simplify-rtx.c (revision 229084)
+++ gcc/simplify-rtx.c (working copy)
@@ -2001,7 +2001,17 @@
tem = simplify_const_binary_operation (code, mode, trueop0, trueop1);
if (tem)
return tem;
- return simplify_binary_operation_1 (code, mode, op0, op1, trueop0, trueop1);
+ tem = simplify_binary_operation_1 (code, mode, op0, op1, trueop0, trueop1);
+
+ if (tem)
+ return tem;
+
+ /* If the above steps did not result in a simplification and op0 or op1
+ were constant pool references, use the referenced constants directly. */
+ if (trueop0 != op0 || trueop1 != op1)
+ return simplify_gen_binary (code, mode, trueop0, trueop1);
+
+ return NULL_RTX;
}
/* Subroutine of simplify_binary_operation. Simplify a binary operation
