[ARM64] Prefer generation of bzero on Darwin only

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207760 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM64/ARM64Subtarget.cpp b/lib/Target/ARM64/ARM64Subtarget.cpp
index 62a489fd86f8eb92ea384afc01b037640a066488..528cfc97cbf704e27e990dfb9499d3628bbd25a0 100644 (file)
--- a/lib/Target/ARM64/ARM64Subtarget.cpp
+++ b/lib/Target/ARM64/ARM64Subtarget.cpp
@@ -90,8 +90,11 @@ ARM64Subtarget::ClassifyGlobalReference(const GlobalValue *GV,
 /// memset with zero passed as the second argument. Otherwise it
 /// returns null.
 const char *ARM64Subtarget::getBZeroEntry() const {
-  // At the moment, always prefer bzero.
-  return "bzero";
+  // Prefer bzero on Darwin only.
+  if(isTargetDarwin())
+    return "bzero";
+
+  return nullptr;
 }
 
 void ARM64Subtarget::overrideSchedPolicy(MachineSchedPolicy &Policy,

diff --git a/test/CodeGen/ARM64/memset-to-bzero.ll b/test/CodeGen/ARM64/memset-to-bzero.ll
index b28122cccd75385f379cb55a0de7d49170f7f7e2..29036caabf3a40f36f7b6741bc88349e890054ef 100644 (file)
--- a/test/CodeGen/ARM64/memset-to-bzero.ll
+++ b/test/CodeGen/ARM64/memset-to-bzero.ll
@@ -1,4 +1,7 @@
-; RUN: llc %s -march arm64 -o - | FileCheck %s
+; RUN: llc %s -mtriple=arm64-apple-darwin -o - | \
+; RUN:   FileCheck --check-prefix=CHECK-DARWIN --check-prefix=CHECK %s
+; RUN: llc %s -mtriple=arm64-linux-gnu -o - | \
+; RUN:   FileCheck --check-prefix=CHECK-LINUX --check-prefix=CHECK %s
 ; <rdar://problem/14199482> ARM64: Calls to bzero() replaced with calls to memset()
 
 ; CHECK: @fct1
@@ -14,7 +17,8 @@ declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1)
 
 ; CHECK: @fct2
 ; When the size is bigger than 256, change into bzero.
-; CHECK: bzero
+; CHECK-DARWIN: bzero
+; CHECK-LINUX: memset
 define void @fct2(i8* nocapture %ptr) {
 entry:
   tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 257, i32 1, i1 false)
@@ -23,7 +27,8 @@ entry:
 
 ; CHECK: @fct3
 ; For unknown size, change to bzero.
-; CHECK: bzero
+; CHECK-DARWIN: bzero
+; CHECK-LINUX: memset
 define void @fct3(i8* nocapture %ptr, i32 %unknown) {
 entry:
   %conv = sext i32 %unknown to i64
@@ -47,7 +52,8 @@ declare i64 @llvm.objectsize.i64(i8*, i1)
 
 ; CHECK: @fct5
 ; Size > 256, change.
-; CHECK: bzero
+; CHECK-DARWIN: bzero
+; CHECK-LINUX: memset
 define void @fct5(i8* %ptr) {
 entry:
   %tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
@@ -57,7 +63,8 @@ entry:
 
 ; CHECK: @fct6
 ; Size = unknown, change.
-; CHECK: bzero
+; CHECK-DARWIN: bzero
+; CHECK-LINUX: memset
 define void @fct6(i8* %ptr, i32 %unknown) {
 entry:
   %conv = sext i32 %unknown to i64