Do not honor explicit alignment attribute on fields for PS4.

This change reverts r257462 for PS4 triple.

Differential Revision: http://reviews.llvm.org/D16788

llvm-svn: 259916

3 files changed, 9 insertions, 2 deletions

diff --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index 0572ff6b134..b8891cb388e 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -1600,7 +1600,8 @@ void ItaniumRecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
         (AllowPadding &&
          (FieldOffset & (FieldAlign-1)) + FieldSize > TypeSize)) {
       FieldOffset = llvm::alignTo(FieldOffset, FieldAlign);
-    } else if (ExplicitFieldAlign) {
+    } else if (ExplicitFieldAlign &&
+               Context.getTargetInfo().useExplicitBitFieldAlignment()) {
       // TODO: figure it out what needs to be done on targets that don't honor
       // bit-field type alignment like ARM APCS ABI.
       FieldOffset = llvm::alignTo(FieldOffset, ExplicitFieldAlign);
@@ -1612,7 +1613,8 @@ void ItaniumRecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
          (UnpackedFieldOffset & (UnpackedFieldAlign-1)) + FieldSize > TypeSize))
       UnpackedFieldOffset =
           llvm::alignTo(UnpackedFieldOffset, UnpackedFieldAlign);
-    else if (ExplicitFieldAlign)
+    else if (ExplicitFieldAlign &&
+             Context.getTargetInfo().useExplicitBitFieldAlignment())
       UnpackedFieldOffset =
           llvm::alignTo(UnpackedFieldOffset, ExplicitFieldAlign);
   }
diff --git a/clang/lib/Basic/TargetInfo.cpp b/clang/lib/Basic/TargetInfo.cpp
index 1648a27d8b3..4a2341e565e 100644
--- a/clang/lib/Basic/TargetInfo.cpp
+++ b/clang/lib/Basic/TargetInfo.cpp
@@ -66,6 +66,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   UseSignedCharForObjCBool = true;
   UseBitFieldTypeAlignment = true;
   UseZeroLengthBitfieldAlignment = false;
+  UseExplicitBitFieldAlignment = true;
   ZeroLengthBitfieldBoundary = 0;
   HalfFormat = &llvm::APFloat::IEEEhalf;
   FloatFormat = &llvm::APFloat::IEEEsingle;
diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 1c05eeef841..cbbf51be18e 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -606,6 +606,10 @@ public:
     this->MaxTLSAlign = 256;
     this->UserLabelPrefix = "";
 
+    // On PS4, do not honor explicit bit field alignment,
+    // as in "__attribute__((aligned(2))) int b : 1;".
+    this->UseExplicitBitFieldAlignment = false;
+
     switch (Triple.getArch()) {
     default:
     case llvm::Triple::x86_64: