compiler: use builtin memcmp directly

Instead of going through a C function __go_memcmp, we can just
    use __builtin_memcmp directly. This allows more optimizations in
    the compiler backend.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/183537

From-SVN: r272620
This commit is contained in:
Ian Lance Taylor 2019-06-24 16:54:22 +00:00
parent 1e3d475ea1
commit 2b92d5c69b
6 changed files with 6 additions and 23 deletions

View File

@ -1,4 +1,4 @@
1232eef628227ef855c5fa6d94b31778b2e74a85
338e4baf88a4ae676205dff601dbef2d31b19d2d
The first line of this file holds the git revision number of the last
merge done from the gofrontend repository.

View File

@ -6199,7 +6199,8 @@ Binary_expression::lower_compare_to_memcmp(Gogo*, Statement_inserter* inserter)
TYPE_INFO_SIZE);
Expression* call = Runtime::make_call(Runtime::MEMCMP, loc, 3, a1, a2, len);
Expression* zero = Expression::make_integer_ul(0, NULL, loc);
Type* int32_type = Type::lookup_integer_type("int32");
Expression* zero = Expression::make_integer_ul(0, int32_type, loc);
return Expression::make_binary(this->op_, call, zero, loc);
}

View File

@ -29,7 +29,7 @@
// result types.
// The standard C memcmp function, used for struct comparisons.
DEF_GO_RUNTIME(MEMCMP, "__go_memcmp", P3(POINTER, POINTER, UINTPTR), R1(INT))
DEF_GO_RUNTIME(MEMCMP, "__builtin_memcmp", P3(POINTER, POINTER, UINTPTR), R1(INT32))
// Decode a non-ASCII rune from a string.
DEF_GO_RUNTIME(DECODERUNE, "runtime.decoderune", P2(STRING, INT),

View File

@ -459,7 +459,6 @@ runtime_files = \
runtime/go-fieldtrack.c \
runtime/go-matherr.c \
runtime/go-memclr.c \
runtime/go-memcmp.c \
runtime/go-memequal.c \
runtime/go-nanotime.c \
runtime/go-now.c \

View File

@ -244,8 +244,8 @@ am__objects_3 = runtime/aeshash.lo runtime/go-assert.lo \
runtime/go-cgo.lo runtime/go-construct-map.lo \
runtime/go-ffi.lo runtime/go-fieldtrack.lo \
runtime/go-matherr.lo runtime/go-memclr.lo \
runtime/go-memcmp.lo runtime/go-memequal.lo \
runtime/go-nanotime.lo runtime/go-now.lo runtime/go-nosys.lo \
runtime/go-memequal.lo runtime/go-nanotime.lo \
runtime/go-now.lo runtime/go-nosys.lo \
runtime/go-reflect-call.lo runtime/go-runtime-error.lo \
runtime/go-setenv.lo runtime/go-signal.lo \
runtime/go-unsafe-pointer.lo runtime/go-unsetenv.lo \
@ -892,7 +892,6 @@ runtime_files = \
runtime/go-fieldtrack.c \
runtime/go-matherr.c \
runtime/go-memclr.c \
runtime/go-memcmp.c \
runtime/go-memequal.c \
runtime/go-nanotime.c \
runtime/go-now.c \
@ -1343,8 +1342,6 @@ runtime/go-matherr.lo: runtime/$(am__dirstamp) \
runtime/$(DEPDIR)/$(am__dirstamp)
runtime/go-memclr.lo: runtime/$(am__dirstamp) \
runtime/$(DEPDIR)/$(am__dirstamp)
runtime/go-memcmp.lo: runtime/$(am__dirstamp) \
runtime/$(DEPDIR)/$(am__dirstamp)
runtime/go-memequal.lo: runtime/$(am__dirstamp) \
runtime/$(DEPDIR)/$(am__dirstamp)
runtime/go-nanotime.lo: runtime/$(am__dirstamp) \
@ -1436,7 +1433,6 @@ distclean-compile:
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-fieldtrack.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-matherr.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-memclr.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-memcmp.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-memequal.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-nanotime.Plo@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@runtime/$(DEPDIR)/go-nosys.Plo@am__quote@

View File

@ -1,13 +0,0 @@
/* go-memcmp.c -- the go memory comparison function.
Copyright 2012 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include "runtime.h"
intgo
__go_memcmp (const void *p1, const void *p2, uintptr len)
{
return __builtin_memcmp (p1, p2, len);
}