From d9cc09721547257ffda45d82a384ef8b225fb9e5 Mon Sep 17 00:00:00 2001 From: xguo Date: Wed, 22 Apr 2015 07:21:35 +0000 Subject: [PATCH] gcc/ChangeLog: 2015-04-22 Hale Wang Terry Guo PR rtl-optimization/64818 * combine.c (can_combine_p): Don't combine user-specified register if it is in an asm input. gcc/testsuite/ChangeLog 2015-04-22 Hale Wang Terry Guo PR rtl-optimization/64818 * gcc.target/arm/pr64818.c: New test. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@222306 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 7 +++++++ gcc/combine.c | 9 +++++++++ gcc/testsuite/ChangeLog | 6 ++++++ gcc/testsuite/gcc.target/arm/pr64818.c | 30 ++++++++++++++++++++++++++++++ 4 files changed, 52 insertions(+) create mode 100644 gcc/testsuite/gcc.target/arm/pr64818.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6959c06..2755252 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2015-04-22 Hale Wang + Terry Guo + + PR rtl-optimization/64818 + * combine.c (can_combine_p): Don't combine user-specified + register if it is in an asm input. + 2015-04-21 Jan Hubicka PR ipa/65076 diff --git a/gcc/combine.c b/gcc/combine.c index 6f0007a..6cd55dd 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -1910,6 +1910,15 @@ can_combine_p (rtx_insn *insn, rtx_insn *i3, rtx_insn *pred ATTRIBUTE_UNUSED, set = expand_field_assignment (set); src = SET_SRC (set), dest = SET_DEST (set); + /* Do not eliminate user-specified register if it is in an + asm input because we may break the register asm usage defined + in GCC manual if allow to do so. + Be aware that this may cover more cases than we expect but this + should be harmless. */ + if (REG_P (dest) && REG_USERVAR_P (dest) && HARD_REGISTER_P (dest) + && extract_asm_operands (PATTERN (i3))) + return 0; + /* Don't eliminate a store in the stack pointer. */ if (dest == stack_pointer_rtx /* Don't combine with an insn that sets a register to itself if it has diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 8b2b177..fd3f700 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2015-04-22 Hale Wang + Terry Guo + + PR rtl-optimization/64818 + * gcc.target/arm/pr64818.c: New test. + 2015-04-21 Jan Hubicka PR ipa/65076 diff --git a/gcc/testsuite/gcc.target/arm/pr64818.c b/gcc/testsuite/gcc.target/arm/pr64818.c new file mode 100644 index 0000000..bddd846 --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/pr64818.c @@ -0,0 +1,30 @@ +/* { dg-do compile } */ +/* { dg-options "-O1" } */ + +char temp[16]; +extern int foo1 (void); + +void foo (void) +{ + int i; + int len; + + while (1) + { + len = foo1 (); + register int a asm ("r0") = 5; + register char *b asm ("r1") = temp; + register int c asm ("r2") = len; + asm volatile ("mov %[r0], %[r0]\n mov %[r1], %[r1]\n mov %[r2], %[r2]\n" + : "+m"(*b) + : [r0]"r"(a), [r1]"r"(b), [r2]"r"(c)); + + for (i = 0; i < len; i++) + { + if (temp[i] == 10) + return; + } + } +} + +/* { dg-final { scan-assembler "\[\\t \]+mov\ r1,\ r1" } } */ -- 2.7.4