Message ID | 20180410135033.GG8577@tucnak |
---|---|
State | New |
Headers | show |
Series | Fix combiner ICE with -g (PR rtl-optimization/85300) | expand |
Hi Jakub, On Tue, Apr 10, 2018 at 03:50:33PM +0200, Jakub Jelinek wrote: > The following testcase ICEs, because subst first creates invalid RTL > (in this case (float:SF (const_int 256))) and only later on simplifies it > using on the-side op0_mode. In the end try_combine succeeds, so we don't > undo anything from the undo buffer, but call propagate_for_debug with the > patterns that were partially modified by subst and ICE on those. > subst already has code to deal with ZERO_EXTEND, this patch just handles > FLOAT and UNSIGNED_FLOAT the same; that way we don't create the invalid > RTL. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Yes please. And thanks for the explanation! Segher > 2018-04-10 Jakub Jelinek <jakub@redhat.com> > > PR rtl-optimization/85300 > * combine.c (subst): Handle subst of CONST_SCALAR_INT_P new_rtx also > into FLOAT and UNSIGNED_FLOAT like ZERO_EXTEND, return a CLOBBER if > simplify_unary_operation fails. > > * gcc.dg/pr85300.c: New test.
--- gcc/combine.c.jj 2018-04-09 20:15:43.704632013 +0200 +++ gcc/combine.c 2018-04-10 09:06:25.826606396 +0200 @@ -5575,11 +5575,15 @@ subst (rtx x, rtx from, rtx to, int in_d x = gen_rtx_CLOBBER (mode, const0_rtx); } else if (CONST_SCALAR_INT_P (new_rtx) - && GET_CODE (x) == ZERO_EXTEND) + && (GET_CODE (x) == ZERO_EXTEND + || GET_CODE (x) == FLOAT + || GET_CODE (x) == UNSIGNED_FLOAT)) { - x = simplify_unary_operation (ZERO_EXTEND, GET_MODE (x), - new_rtx, GET_MODE (XEXP (x, 0))); - gcc_assert (x); + x = simplify_unary_operation (GET_CODE (x), GET_MODE (x), + new_rtx, + GET_MODE (XEXP (x, 0))); + if (!x) + return gen_rtx_CLOBBER (VOIDmode, const0_rtx); } else SUBST (XEXP (x, i), new_rtx); --- gcc/testsuite/gcc.dg/pr85300.c.jj 2018-04-10 08:53:04.594782804 +0200 +++ gcc/testsuite/gcc.dg/pr85300.c 2018-04-10 08:53:04.594782804 +0200 @@ -0,0 +1,16 @@ +/* PR rtl-optimization/85300 */ +/* { dg-do compile } */ +/* { dg-options "-O1 -g -funroll-all-loops -fno-tree-ter -fno-web" } */ + +void +foo (double x, unsigned char y) +{ + while ((int) x < 1) + { + float a; + + a = y | 0x100; + y = 0; + x = a; + } +}