From b494b18a5f1ea9df93a3bff84316def817c04bc7 Mon Sep 17 00:00:00 2001 From: Kyrylo Tkachov Date: Wed, 9 Jul 2025 10:04:01 -0700 Subject: [PATCH] aarch64: PR target/120999: Adjust operands for movprfx alternative of NBSL implementation of NOR While the SVE2 NBSL instruction accepts MOVPRFX to add more flexibility due to its tied operands, the destination of the movprfx cannot be also a source operand. But the offending pattern in aarch64-sve2.md tries to do exactly that for the "=?&w,w,w" alternative and gas warns for the attached testcase. This patch adjusts that alternative to avoid taking operand 0 as an input in the NBSL again. So for the testcase in the patch we now generate: nor_z: movprfx z0, z1 nbsl z0.d, z0.d, z2.d, z1.d ret instead of the previous: nor_z: movprfx z0, z1 nbsl z0.d, z0.d, z2.d, z0.d ret which generated a gas warning. Bootstrapped and tested on aarch64-none-linux-gnu. Signed-off-by: Kyrylo Tkachov gcc/ PR target/120999 * config/aarch64/aarch64-sve2.md (*aarch64_sve2_nor): Adjust movprfx alternative. gcc/testsuite/ PR target/120999 * gcc.target/aarch64/sve2/pr120999.c: New test. --- gcc/config/aarch64/aarch64-sve2.md | 2 +- .../gcc.target/aarch64/sve2/pr120999.c | 17 +++++++++++++++++ 2 files changed, 18 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.target/aarch64/sve2/pr120999.c diff --git a/gcc/config/aarch64/aarch64-sve2.md b/gcc/config/aarch64/aarch64-sve2.md index 15714712d3b..256eb198c55 100644 --- a/gcc/config/aarch64/aarch64-sve2.md +++ b/gcc/config/aarch64/aarch64-sve2.md @@ -1628,7 +1628,7 @@ "TARGET_SVE2" {@ [ cons: =0 , %1 , 2 ; attrs: movprfx ] [ w , 0 , w ; * ] nbsl\t%0.d, %0.d, %2.d, %0.d - [ ?&w , w , w ; yes ] movprfx\t%0, %1\;nbsl\t%0.d, %0.d, %2.d, %0.d + [ ?&w , w , w ; yes ] movprfx\t%0, %1\;nbsl\t%0.d, %0.d, %2.d, %1.d } "&& !CONSTANT_P (operands[3])" { diff --git a/gcc/testsuite/gcc.target/aarch64/sve2/pr120999.c b/gcc/testsuite/gcc.target/aarch64/sve2/pr120999.c new file mode 100644 index 00000000000..2dca36aea22 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/sve2/pr120999.c @@ -0,0 +1,17 @@ +/* PR target/120999. */ +/* { dg-do assemble } */ +/* { dg-options "-O2 --save-temps" } */ +/* { dg-final { check-function-bodies "**" "" "" } } */ + +#include + +#define NOR(x, y) (~((x) | (y))) + +/* +** nor_z: +** movprfx z0, z1 +** nbsl z0.d, z0.d, z2.d, z1.d +** ret +*/ +svuint64_t nor_z(svuint64_t c, svuint64_t a, svuint64_t b) { return NOR(a, b); } + -- 2.44.0