Just like CONST_INT, CONST_WIDE_INT is VOIDmode, so LRA might be tempted to build a SUBREG to "convert" it to the wanted mode. That's no use. Test for CONST_SCALAR_INT_P instead of CONST_INT_P so that we skip the subreg creation for both.
Regstrapped on x86_64- and i686-linux-gnu. Ok to install? for gcc/ChangeLog PR rtl-optimization/87874 * lra.c (lra_substitute_pseudo): Do not create a subreg for const wide ints. for gcc/testsuite/ChangeLog PR rtl-optimization/87874 * gcc.dg/pr87874.c: New. --- gcc/lra.c | 2 +- gcc/testsuite/gcc.dg/pr87874.c | 35 +++++++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/pr87874.c diff --git a/gcc/lra.c b/gcc/lra.c index aa768fb2a231..5d58d90f3a6b 100644 --- a/gcc/lra.c +++ b/gcc/lra.c @@ -1961,7 +1961,7 @@ lra_substitute_pseudo (rtx *loc, int old_regno, rtx new_reg, bool subreg_p, machine_mode inner_mode = GET_MODE (new_reg); if (mode != inner_mode - && ! (CONST_INT_P (new_reg) && SCALAR_INT_MODE_P (mode))) + && ! (CONST_SCALAR_INT_P (new_reg) && SCALAR_INT_MODE_P (mode))) { poly_uint64 offset = 0; if (partial_subreg_p (mode, inner_mode) diff --git a/gcc/testsuite/gcc.dg/pr87874.c b/gcc/testsuite/gcc.dg/pr87874.c new file mode 100644 index 000000000000..3ab5dcf68ffb --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr87874.c @@ -0,0 +1,35 @@ +/* { dg-do compile } */ +/* { dg-options "-g -O1 -fgcse -fno-dce -fno-tree-ccp -fno-tree-coalesce-vars -fno-tree-copy-prop -fno-tree-dce -fno-tree-dominator-opts -fno-tree-fre -fno-tree-loop-optimize -fno-tree-sink" } */ + +int *vk; +int m2; +#if __SIZEOF_INT128__ +__int128 nb; + +void +em (int u5, int fo, int s7) +{ + for (;;) + { + long int es; + + es = !!u5 ? (!!fo && !!m2) : fo; + if (es == 0) + if (nb == *vk) + { + const unsigned long int uint64_max = 18446744073709551615ul; + __int128 ks = uint64_max / 2 + 1; + + while (s7 < 1) + while (nb < 2) + { + for (ks = 0; ks < 3; ++ks) + { + } + + ++nb; + } + } + } +} +#endif -- Alexandre Oliva, freedom fighter https://FSFLA.org/blogs/lxo Be the change, be Free! FSF Latin America board member GNU Toolchain Engineer Free Software Evangelist Hay que enGNUrecerse, pero sin perder la terGNUra jamás-GNUChe