From 74838de312b5e8abae7c8482d8d7da2268cc9624 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Wed, 25 May 2011 13:42:58 +0000 Subject: [PATCH] Implement x86 pause intrinsic. gcc/ 2011-05-25 H.J. Lu * config/i386/i386.c (ix86_builtins): Add IX86_BUILTIN_PAUSE. (bdesc_special_args): Add pause intrinsic. * config/i386/i386.md (UNSPEC_PAUSE): New. (pause): Likewise. (*pause): Likewise. * config/i386/ia32intrin.h (__pause): Likewise. * doc/extend.texi (X86 Built-in Functions): Add documentation for pause intrinsic. gcc/testsuite/ 2011-05-25 H.J. Lu * gcc.target/i386/pause-1.c: New. From-SVN: r174197 --- gcc/ChangeLog | 13 +++++++++++++ gcc/config/i386/i386.c | 2 ++ gcc/config/i386/i386.md | 20 ++++++++++++++++++++ gcc/config/i386/ia32intrin.h | 8 ++++++++ gcc/doc/extend.texi | 7 +++++++ gcc/testsuite/ChangeLog | 4 ++++ gcc/testsuite/gcc.target/i386/pause-1.c | 11 +++++++++++ 7 files changed, 65 insertions(+) create mode 100644 gcc/testsuite/gcc.target/i386/pause-1.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1fc7adb540f..873de192831 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,16 @@ +2011-05-25 H.J. Lu + + * config/i386/i386.c (ix86_builtins): Add IX86_BUILTIN_PAUSE. + (bdesc_special_args): Add pause intrinsic. + + * config/i386/i386.md (UNSPEC_PAUSE): New. + (pause): Likewise. + (*pause): Likewise. + * config/i386/ia32intrin.h (__pause): Likewise. + + * doc/extend.texi (X86 Built-in Functions): Add documentation for + pause intrinsic. + 2011-05-25 Bill Schmidt PR tree-optimization/46728 diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 4b5bc96c492..c7da6d3f26e 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -23912,6 +23912,7 @@ enum ix86_builtins IX86_BUILTIN_CLFLUSH, IX86_BUILTIN_MFENCE, IX86_BUILTIN_LFENCE, + IX86_BUILTIN_PAUSE, IX86_BUILTIN_BSRSI, IX86_BUILTIN_BSRDI, @@ -24664,6 +24665,7 @@ static const struct builtin_description bdesc_special_args[] = { { ~OPTION_MASK_ISA_64BIT, CODE_FOR_rdtsc, "__builtin_ia32_rdtsc", IX86_BUILTIN_RDTSC, UNKNOWN, (int) UINT64_FTYPE_VOID }, { ~OPTION_MASK_ISA_64BIT, CODE_FOR_rdtscp, "__builtin_ia32_rdtscp", IX86_BUILTIN_RDTSCP, UNKNOWN, (int) UINT64_FTYPE_PUNSIGNED }, + { ~OPTION_MASK_ISA_64BIT, CODE_FOR_pause, "__builtin_ia32_pause", IX86_BUILTIN_PAUSE, UNKNOWN, (int) VOID_FTYPE_VOID }, /* MMX */ { OPTION_MASK_ISA_MMX, CODE_FOR_mmx_emms, "__builtin_ia32_emms", IX86_BUILTIN_EMMS, UNKNOWN, (int) VOID_FTYPE_VOID }, diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index 49f1ee747fc..801573c1e98 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -108,6 +108,7 @@ UNSPEC_TRUNC_NOOP UNSPEC_DIV_ALREADY_SPLIT UNSPEC_CALL_NEEDS_VZEROUPPER + UNSPEC_PAUSE ;; For SSE/MMX support: UNSPEC_FIX_NOTRUNC @@ -17716,6 +17717,25 @@ [(set_attr "type" "other") (set_attr "prefix_extra" "1")]) +(define_expand "pause" + [(set (match_dup 0) + (unspec:BLK [(match_dup 0)] UNSPEC_PAUSE))] + "" +{ + operands[0] = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode)); + MEM_VOLATILE_P (operands[0]) = 1; +}) + +;; Use "rep; nop", instead of "pause", to support older assemblers. +;; They have the same encoding. +(define_insn "*pause" + [(set (match_operand:BLK 0 "" "") + (unspec:BLK [(match_dup 0)] UNSPEC_PAUSE))] + "" + "rep; nop" + [(set_attr "length" "2") + (set_attr "memory" "unknown")]) + (include "mmx.md") (include "sse.md") (include "sync.md") diff --git a/gcc/config/i386/ia32intrin.h b/gcc/config/i386/ia32intrin.h index 76c20a69a90..42ebd17cdbb 100644 --- a/gcc/config/i386/ia32intrin.h +++ b/gcc/config/i386/ia32intrin.h @@ -153,6 +153,14 @@ __rord (unsigned int __X, int __C) return (__X >> __C) | (__X << (32 - __C)); } +/* Pause */ +extern __inline void +__attribute__((__gnu_inline__, __always_inline__, __artificial__)) +__pause (void) +{ + __builtin_ia32_pause (); +} + #ifdef __x86_64__ /* 64bit bsf */ extern __inline int diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index b5702dbf7d8..bd2f08023ea 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -8695,6 +8695,13 @@ __float128 __builtin_fabsq (__float128) __float128 __builtin_copysignq (__float128, __float128) @end smallexample +The following built-in function is always available. + +@table @code +@item void __builtin_ia32_pause (void) +Generates the @code{pause} machine instruction with full memory barrier. +@end table + The following floating point built-in functions are made available in the 64-bit mode. diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 7e1878504f7..4258b91106c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2011-05-25 H.J. Lu + + * gcc.target/i386/pause-1.c: New. + 2011-05-25 Eric Botcazou * gcc.dg/stack-usage-1.c: Adjust comment. diff --git a/gcc/testsuite/gcc.target/i386/pause-1.c b/gcc/testsuite/gcc.target/i386/pause-1.c new file mode 100644 index 00000000000..50eb8e7e2fb --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pause-1.c @@ -0,0 +1,11 @@ +/* Test that we generate pause instruction. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -dp" } */ +/* { dg-final { scan-assembler-times "\\*pause" 1 } } */ + +#include + +void foo(void) +{ + __pause(); +}