From 8e02e8a0a588d0dbd64c375dd604fecc8fde2f83 Mon Sep 17 00:00:00 2001 From: Matthew Fortune Date: Tue, 31 Oct 2017 18:27:52 +0000 Subject: [PATCH] re PR rtl-optimization/81803 (miscompilation at -O1 on mips64el) PR rtl-optimization/81803 * lra-constraints.c (curr_insn_transform): Also reload the whole register for a strict subreg no wider than a word if this is for a WORD_REGISTER_OPERATIONS target. Co-Authored-By: Eric Botcazou From-SVN: r254275 --- gcc/ChangeLog | 8 ++++++++ gcc/lra-constraints.c | 11 ++++++++--- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 3ed1c09..b73c5c6 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2017-10-31 Matthew Fortune + Eric Botcazou + + PR rtl-optimization/81803 + * lra-constraints.c (curr_insn_transform): Also reload the whole + register for a strict subreg no wider than a word if this is for + a WORD_REGISTER_OPERATIONS target. + 2017-10-31 Jason Merrill * gdbinit.in: Skip over inlines from timevar.h. diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c index a423f06..3758409 100644 --- a/gcc/lra-constraints.c +++ b/gcc/lra-constraints.c @@ -4207,8 +4207,9 @@ curr_insn_transform (bool check_only_p) reg = SUBREG_REG (*loc); byte = SUBREG_BYTE (*loc); if (REG_P (reg) - /* Strict_low_part requires reload the register not - the sub-register. */ + /* Strict_low_part requires reloading the register and not + just the subreg. Likewise for a strict subreg no wider + than a word for WORD_REGISTER_OPERATIONS targets. */ && (curr_static_id->operand[i].strict_low || (!paradoxical_subreg_p (mode, GET_MODE (reg)) && (hard_regno @@ -4219,7 +4220,11 @@ curr_insn_transform (bool check_only_p) && (goal_alt[i] == NO_REGS || (simplify_subreg_regno (ira_class_hard_regs[goal_alt[i]][0], - GET_MODE (reg), byte, mode) >= 0))))) + GET_MODE (reg), byte, mode) >= 0))) + || (GET_MODE_PRECISION (mode) + < GET_MODE_PRECISION (GET_MODE (reg)) + && GET_MODE_SIZE (GET_MODE (reg)) <= UNITS_PER_WORD + && WORD_REGISTER_OPERATIONS))) { /* An OP_INOUT is required when reloading a subreg of a mode wider than a word to ensure that data beyond the -- 2.7.4