tree-optimization/114672 - WIDEN_MULT_PLUS_EXPR type mismatch

The following makes sure to restrict WIDEN_MULT*_EXPR to a mode
precision final compute type as the mode is used to find the optab
and type checking chokes when seeing bit-precisions later which
would likely also not properly expanded to RTL.

	PR tree-optimization/114672
	* tree-ssa-math-opts.cc (convert_plusminus_to_widen): Only
	allow mode-precision results.

	* gcc.dg/torture/pr114672.c: New testcase.
This commit is contained in:
Richard Biener 2024-04-10 10:33:40 +02:00
parent 5aa3fec38c
commit 912753cc5f
2 changed files with 17 additions and 2 deletions

View file

@ -0,0 +1,14 @@
/* { dg-do compile } */
struct {
__INT64_TYPE__ m : 60;
} s;
short a;
short b;
void
foo ()
{
s.m += a * b;
}

View file

@ -2918,8 +2918,9 @@ convert_plusminus_to_widen (gimple_stmt_iterator *gsi, gimple *stmt,
lhs = gimple_assign_lhs (stmt);
type = TREE_TYPE (lhs);
if (TREE_CODE (type) != INTEGER_TYPE
&& TREE_CODE (type) != FIXED_POINT_TYPE)
if ((TREE_CODE (type) != INTEGER_TYPE
&& TREE_CODE (type) != FIXED_POINT_TYPE)
|| !type_has_mode_precision_p (type))
return false;
if (code == MINUS_EXPR)