[X86] Extend some Linux special cases to cover kFreeBSD.

Both Linux and kFreeBSD use glibc, so follow similiar code paths.
Add isTargetGlibc to check for this, and use it instead of isTargetLinux
in a few places.

Fixes PR22248 for kFreeBSD.

Differential Revision: http://reviews.llvm.org/D19104

llvm-svn: 268624

7 files changed, 26 insertions, 5 deletions

diff --git a/llvm/include/llvm/ADT/Triple.h b/llvm/include/llvm/ADT/Triple.h
index d163ac7bd77..c89cf4dc2f3 100644
--- a/llvm/include/llvm/ADT/Triple.h
+++ b/llvm/include/llvm/ADT/Triple.h
@@ -523,6 +523,16 @@ public:
     return getOS() == Triple::Linux;
   }
 
+  /// Tests whether the OS is kFreeBSD.
+  bool isOSKFreeBSD() const {
+    return getOS() == Triple::KFreeBSD;
+  }
+
+  /// Tests whether the OS uses glibc.
+  bool isOSGlibc() const {
+    return getOS() == Triple::Linux || getOS() == Triple::KFreeBSD;
+  }
+
   /// Tests whether the OS uses the ELF binary format.
   bool isOSBinFormatELF() const {
     return getObjectFormat() == Triple::ELF;
diff --git a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
index 4fa7a0fccc0..a565a48b5f4 100644
--- a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -719,7 +719,7 @@ bool X86DAGToDAGISel::matchLoadInAddress(LoadSDNode *N, X86ISelAddressMode &AM){
   // For more information see http://people.redhat.com/drepper/tls.pdf
   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Address))
     if (C->getSExtValue() == 0 && AM.Segment.getNode() == nullptr &&
-        Subtarget->isTargetLinux())
+        Subtarget->isTargetGlibc())
       switch (N->getPointerInfo().getAddrSpace()) {
       case 256:
         AM.Segment = CurDAG->getRegister(X86::GS, MVT::i16);
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index d3457ed841f..eeaffe9609a 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -1919,7 +1919,9 @@ unsigned X86TargetLowering::getAddressSpace() const {
 }
 
 Value *X86TargetLowering::getIRStackGuard(IRBuilder<> &IRB) const {
-  if (!Subtarget.isTargetLinux())
+  // glibc has a special slot for the stack guard in tcbhead_t, use it instead
+  // of the usual global variable (see sysdeps/{i386,x86_64}/nptl/tls.h)
+  if (!Subtarget.isTargetGlibc())
     return TargetLowering::getIRStackGuard(IRB);
 
   // %fs:0x28, unless we're using a Kernel code model, in which case it's %gs:
@@ -1932,7 +1934,7 @@ Value *X86TargetLowering::getIRStackGuard(IRBuilder<> &IRB) const {
 }
 
 void X86TargetLowering::insertSSPDeclarations(Module &M) const {
-  if (!Subtarget.isTargetLinux())
+  if (!Subtarget.isTargetGlibc())
     TargetLowering::insertSSPDeclarations(M);
 }
 
diff --git a/llvm/lib/Target/X86/X86Subtarget.cpp b/llvm/lib/Target/X86/X86Subtarget.cpp
index ad7c2578aa9..896856c3489 100644
--- a/llvm/lib/Target/X86/X86Subtarget.cpp
+++ b/llvm/lib/Target/X86/X86Subtarget.cpp
@@ -262,12 +262,12 @@ void X86Subtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
   assert((!In64BitMode || HasX86_64) &&
          "64-bit code requested on a subtarget that doesn't support it!");
 
-  // Stack alignment is 16 bytes on Darwin, Linux and Solaris (both
+  // Stack alignment is 16 bytes on Darwin, Linux, kFreeBSD and Solaris (both
   // 32 and 64 bit) and for all 64-bit targets.
   if (StackAlignOverride)
     stackAlignment = StackAlignOverride;
   else if (isTargetDarwin() || isTargetLinux() || isTargetSolaris() ||
-           In64BitMode)
+           isTargetKFreeBSD() || In64BitMode)
     stackAlignment = 16;
 }
 
diff --git a/llvm/lib/Target/X86/X86Subtarget.h b/llvm/lib/Target/X86/X86Subtarget.h
index 6ffbde2720a..d8cf98b6e2a 100644
--- a/llvm/lib/Target/X86/X86Subtarget.h
+++ b/llvm/lib/Target/X86/X86Subtarget.h
@@ -467,6 +467,8 @@ public:
   bool isTargetMachO() const { return TargetTriple.isOSBinFormatMachO(); }
 
   bool isTargetLinux() const { return TargetTriple.isOSLinux(); }
+  bool isTargetKFreeBSD() const { return TargetTriple.isOSKFreeBSD(); }
+  bool isTargetGlibc() const { return TargetTriple.isOSGlibc(); }
   bool isTargetAndroid() const { return TargetTriple.isAndroid(); }
   bool isTargetNaCl() const { return TargetTriple.isOSNaCl(); }
   bool isTargetNaCl32() const { return isTargetNaCl() && !is64Bit(); }
diff --git a/llvm/test/CodeGen/X86/stack-align2.ll b/llvm/test/CodeGen/X86/stack-align2.ll
index 18cce7266d1..7239198000c 100644
--- a/llvm/test/CodeGen/X86/stack-align2.ll
+++ b/llvm/test/CodeGen/X86/stack-align2.ll
@@ -1,7 +1,9 @@
 ; RUN: llc < %s -mcpu=generic -mtriple=i386-linux | FileCheck %s -check-prefix=LINUX-I386
+; RUN: llc < %s -mcpu=generic -mtriple=i386-kfreebsd | FileCheck %s -check-prefix=KFREEBSD-I386
 ; RUN: llc < %s -mcpu=generic -mtriple=i386-netbsd | FileCheck %s -check-prefix=NETBSD-I386
 ; RUN: llc < %s -mcpu=generic -mtriple=i686-apple-darwin8 | FileCheck %s -check-prefix=DARWIN-I386
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-linux | FileCheck %s -check-prefix=LINUX-X86_64
+; RUN: llc < %s -mcpu=generic -mtriple=x86_64-kfreebsd | FileCheck %s -check-prefix=KFREEBSD-X86_64
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-netbsd | FileCheck %s -check-prefix=NETBSD-X86_64
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-apple-darwin8 | FileCheck %s -check-prefix=DARWIN-X86_64
 
@@ -11,6 +13,7 @@ entry:
   ret i32 0
 
 ; LINUX-I386:     subl	$12, %esp
+; KFREEBSD-I386:  subl	$12, %esp
 ; DARWIN-I386:    subl	$12, %esp
 ; NETBSD-I386-NOT: subl	{{.*}}, %esp
 
@@ -20,6 +23,8 @@ entry:
 ; DARWIN-X86_64-NOT: subq	{{.*}}, %rsp
 ; NETBSD-X86_64:     pushq %{{.*}}
 ; NETBSD-X86_64-NOT: subq	{{.*}}, %rsp
+; KFREEBSD-X86_64:     pushq %{{.*}}
+; KFREEBSD-X86_64-NOT: subq	{{.*}}, %rsp
 }
 
 declare void @test2()
diff --git a/llvm/test/CodeGen/X86/stack-protector-target.ll b/llvm/test/CodeGen/X86/stack-protector-target.ll
index 3f69bfd7e7b..66e45055b2b 100644
--- a/llvm/test/CodeGen/X86/stack-protector-target.ll
+++ b/llvm/test/CodeGen/X86/stack-protector-target.ll
@@ -3,6 +3,8 @@
 ; RUN: llc -mtriple=x86_64-linux < %s -o - | FileCheck --check-prefix=LINUX-X64 %s
 ; RUN: llc -mtriple=i386-linux-android < %s -o - | FileCheck --check-prefix=LINUX-I386 %s
 ; RUN: llc -mtriple=x86_64-linux-android < %s -o - | FileCheck --check-prefix=LINUX-X64 %s
+; RUN: llc -mtriple=i386-kfreebsd < %s -o - | FileCheck --check-prefix=LINUX-I386 %s
+; RUN: llc -mtriple=x86_64-kfreebsd < %s -o - | FileCheck --check-prefix=LINUX-X64 %s
 
 define void @_Z1fv() sspreq {
 entry: