From 9a875db43cd4210843c480c8df26a1d6624d057d Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 18 Jun 2020 12:08:06 +0200 Subject: [PATCH] forwprop: simplify_vector_constructor follow-up fix [PR95713] As the following testcase shows, the exception for the aarch64 vec_pack_trunc_di is not sufficient on x86, the halfvectype "vectors" have SImode but the x86 vec_pack_trunc_si meant for the bool bitmasks combines 2x SImode into DImode, while in the testcase the halfvectype is 1x SImode "vector" with SImode and result is 2x HImode "vector" with SImode. Richard Sandiford's reply: FWIW, since the aarch64 case was only found by inspection and might not be useful, personally I'd prefer to drop that case after all. 2020-06-18 Jakub Jelinek PR target/95713 * tree-ssa-forwprop.c (simplify_vector_constructor): Don't allow scalar mode halfvectype other than vector boolean for VEC_PACK_TRUNC_EXPR. * gcc.dg/pr95713.c: New test. --- gcc/testsuite/gcc.dg/pr95713.c | 15 +++++++++++++++ gcc/tree-ssa-forwprop.c | 11 ++++------- 2 files changed, 19 insertions(+), 7 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr95713.c diff --git a/gcc/testsuite/gcc.dg/pr95713.c b/gcc/testsuite/gcc.dg/pr95713.c new file mode 100644 index 00000000000..b167842b963 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr95713.c @@ -0,0 +1,15 @@ +/* PR target/95713 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wno-psabi -w" } */ +/* { dg-additional-options "-mavx512bw" { target i?86-*-* x86_64-*-* } } */ + +typedef int v2si __attribute__((vector_size (8))); +typedef short int v2hi __attribute__((vector_size (4))); +void foo (v2hi); + +void +bar (v2si x) +{ + v2hi a = (v2hi) { (short) x[0], (short) x[1] }; + foo (4 > a); +} diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index 0ab8267fdf9..a4aed3ccade 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -2401,8 +2401,8 @@ simplify_vector_constructor (gimple_stmt_iterator *gsi) && (dblvectype = build_vector_type (TREE_TYPE (TREE_TYPE (orig[0])), nelts * 2)) - /* Only use it for vector modes or for vector booleans represented - as scalar bitmasks. See PR95528. */ + /* Only use it for vector modes or for vector booleans + represented as scalar bitmasks. See PR95528. */ && (VECTOR_MODE_P (TYPE_MODE (dblvectype)) || VECTOR_BOOLEAN_TYPE_P (dblvectype)) && (optab = optab_for_tree_code (FLOAT_TYPE_P (TREE_TYPE (type)) @@ -2447,12 +2447,9 @@ simplify_vector_constructor (gimple_stmt_iterator *gsi) = build_vector_type (TREE_TYPE (TREE_TYPE (orig[0])), nelts / 2)) /* Only use it for vector modes or for vector booleans - represented as scalar bitmasks, or allow halfvectype - be the element mode. See PR95528. */ + represented as scalar bitmasks. See PR95528. */ && (VECTOR_MODE_P (TYPE_MODE (halfvectype)) - || VECTOR_BOOLEAN_TYPE_P (halfvectype) - || (TYPE_MODE (halfvectype) - == TYPE_MODE (TREE_TYPE (halfvectype)))) + || VECTOR_BOOLEAN_TYPE_P (halfvectype)) && (optab = optab_for_tree_code (VEC_PACK_TRUNC_EXPR, halfvectype, optab_default)) -- 2.30.2