From d13603501680fcdbb933cb086cd01fcc39be1908 Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 4 Nov 2021 09:17:18 +0100 Subject: [PATCH] rtl-optimization/103075 - avoid ICEing on unfolded int-to-float converts The following avoids asserting in exact_int_to_float_conversion_p that the argument is not constant which it in fact can be with -frounding-math and inexact int-to-float conversions. Say so. 2021-11-04 Richard Biener PR rtl-optimization/103075 * simplify-rtx.c (exact_int_to_float_conversion_p): Return false for a VOIDmode operand. * gcc.dg/pr103075.c: New testcase. --- gcc/simplify-rtx.c | 8 +++++--- gcc/testsuite/gcc.dg/pr103075.c | 8 ++++++++ 2 files changed, 13 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr103075.c diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 9038affa036..eea747664d4 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -899,10 +899,12 @@ simplify_context::simplify_unary_operation (rtx_code code, machine_mode mode, static bool exact_int_to_float_conversion_p (const_rtx op) { - int out_bits = significand_size (GET_MODE_INNER (GET_MODE (op))); machine_mode op0_mode = GET_MODE (XEXP (op, 0)); - /* Constants shouldn't reach here. */ - gcc_assert (op0_mode != VOIDmode); + /* Constants can reach here with -frounding-math, if they do then + the conversion isn't exact. */ + if (op0_mode == VOIDmode) + return false; + int out_bits = significand_size (GET_MODE_INNER (GET_MODE (op))); int in_prec = GET_MODE_UNIT_PRECISION (op0_mode); int in_bits = in_prec; if (HWI_COMPUTABLE_MODE_P (op0_mode)) diff --git a/gcc/testsuite/gcc.dg/pr103075.c b/gcc/testsuite/gcc.dg/pr103075.c new file mode 100644 index 00000000000..b332fb01434 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr103075.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-options "-O -frounding-math" } */ + +float +foo (void) +{ + return (float) 0x1699925 * 1.1; +}