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[PATCH] FMA_EXPR can cause -fnon-call-exceptions with floating point args (PR middle-end/79396)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Richard Biener <rguenther at suse dot de>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Fri, 24 Feb 2017 21:56:25 +0100
- Subject: [PATCH] FMA_EXPR can cause -fnon-call-exceptions with floating point args (PR middle-end/79396)
- Authentication-results: sourceware.org; auth=none
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
On the following testcase we replace a PLUS_EXPR (which is considered
throwing with -fnon-call-exceptions when it has floating point arguments
and FP exceptions or sNaNs are enabled) with a FMA_EXPR; I believe it
can throw the same, but stmt_could_throw_1_p doesn't think so (as it is
not unary/binary/comparison). While we could tweak the widen_mul patch
to deal with dropping EH from gsi_replace and cleaning up cfg etc., I
believe the right fix is to fix stmt_could_throw_1_p.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2017-02-24 Jakub Jelinek <jakub@redhat.com>
PR middle-end/79396
* tree-eh.c (stmt_could_throw_1_p): Handle FMA_EXPR like tcc_binary
or tcc_unary.
* g++.dg/opt/pr79396.C: New test.
--- gcc/tree-eh.c.jj 2017-02-06 13:32:13.000000000 +0100
+++ gcc/tree-eh.c 2017-02-24 19:14:04.964854279 +0100
@@ -2738,7 +2738,8 @@ stmt_could_throw_1_p (gimple *stmt)
if (TREE_CODE_CLASS (code) == tcc_comparison
|| TREE_CODE_CLASS (code) == tcc_unary
- || TREE_CODE_CLASS (code) == tcc_binary)
+ || TREE_CODE_CLASS (code) == tcc_binary
+ || code == FMA_EXPR)
{
if (is_gimple_assign (stmt)
&& TREE_CODE_CLASS (code) == tcc_comparison)
--- gcc/testsuite/g++.dg/opt/pr79396.C.jj 2017-02-24 19:22:18.499312974 +0100
+++ gcc/testsuite/g++.dg/opt/pr79396.C 2017-02-24 19:21:38.000000000 +0100
@@ -0,0 +1,13 @@
+// PR middle-end/79396
+// { dg-do compile }
+// { dg-options "-fnon-call-exceptions -O2" }
+// { dg-additional-options "-mfma" { target i?86-*-* x86_64-*-* } }
+
+struct A { A (); ~A (); };
+
+float
+foo (float x)
+{
+ A a;
+ return __builtin_pow (x, 2) + 2;
+}
Jakub