Hi Kewen,
Thanks a lot for your very helpful comments!
On 2023-04-10 17:26, Kewen.Lin wrote:
Hi Jeff,
on 2023/4/10 10:09, Jiufu Guo via Gcc-patches wrote:
Hi,
In this test case (float128-cmp2-runnable.c), the instruction
xscmpexpqp is used to support a few builtins e.g.
__builtin_vsx_scalar_cmp_exp_qp_eq on _Float128.
This instruction handles the whole 128bits of the vector, and
it is guarded by [ieee128-hw].
The instruction xscmpexpqp is guarded with TARGET_P9_VECTOR,
(define_insn "*xscmpexpqp"
[(set (match_operand:CCFP 0 "cc_reg_operand" "=y")
(compare:CCFP
(unspec:IEEE128 [(match_operand:IEEE128 1 "altivec_register_operand"
"v")
(match_operand:IEEE128 2 "altivec_register_operand"
"v")]
UNSPEC_VSX_SCMPEXPQP)
(match_operand:SI 3 "zero_constant" "j")))]
"TARGET_P9_VECTOR"
"xscmpexpqp %0,%1,%2"
[(set_attr "type" "fpcompare")])
[ieee128-hw] is used for guarding those bifs, so the above
statement doesn't quite match the fact.
Agree, I'm wondering if P9_VECTOR is perfect here, even if it indicates
the ISA
which contains xscmpexpqp. Let me have more checks.
PR108758 said this case doesn't fail with gcc-10 and gcc-11,
I wonder why it changes from gcc-12? The above define_insn
shows the underlying insns for these bifs just requires the
condition power9-vector. Could you have a further check?
Thanks.
Thanks for raising this concern.
The behavior to check about bif on FLOAT128_HW and emit an error message
for
requirements on quad-precision is added in gcc12. This is why gcc12
fails to
compile the case on -m32.
Before gcc12, altivec_resolve_overloaded_builtin will return the
overloaded
result directly, and does not check more about the result function.
btw, please add a PR marker for PR108758.
Sure, thanks for catching this!
BR,
Jeff (Jiufu)
BR,
Kewen
So, we may update the testcase to require ppc_float128_hw.
Tested on ppc64 both BE and LE.
Is this ok for trunk?
BR,
Jeff (Jiufu)
gcc/testsuite/ChangeLog:
* gcc.target/powerpc/float128-cmp2-runnable.c: Update requires.
---
gcc/testsuite/gcc.target/powerpc/float128-cmp2-runnable.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/testsuite/gcc.target/powerpc/float128-cmp2-runnable.c
b/gcc/testsuite/gcc.target/powerpc/float128-cmp2-runnable.c
index d376a3ca68e..91287c0fb7a 100644
--- a/gcc/testsuite/gcc.target/powerpc/float128-cmp2-runnable.c
+++ b/gcc/testsuite/gcc.target/powerpc/float128-cmp2-runnable.c
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-require-effective-target ppc_float128_sw } */
+/* { dg-require-effective-target ppc_float128_hw } */
/* { dg-require-effective-target p9vector_hw } */
/* { dg-options "-O2 -mdejagnu-cpu=power9 " } */
