[Clang] Don't adjust align for IBM extended double

Commit 6b1341eb fixed alignment for 128-bit FP types on PowerPC.
However, the quadword alignment adjustment shouldn't be applied to IBM
extended double (ppc_fp128 in IR) values.

Reviewed By: jsji

Differential Revision: https://reviews.llvm.org/D92278

1 files changed, 6 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 3469bc6..48152663 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -5052,10 +5052,12 @@ CharUnits PPC64_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
     return CharUnits::fromQuantity(16);
   } else if (Ty->isVectorType()) {
     return CharUnits::fromQuantity(getContext().getTypeSize(Ty) == 128 ? 16 : 8);
-  } else if (Ty->isRealFloatingType() && getContext().getTypeSize(Ty) == 128) {
-    // IEEE 128-bit floating numbers are also stored in vector registers.
-    // And both IEEE quad-precision and IBM extended double (ppc_fp128) should
-    // be quad-word aligned.
+  } else if (Ty->isRealFloatingType() &&
+             &getContext().getFloatTypeSemantics(Ty) ==
+                 &llvm::APFloat::IEEEquad()) {
+    // According to ABI document section 'Optional Save Areas': If extended
+    // precision floating-point values in IEEE BINARY 128 QUADRUPLE PRECISION
+    // format are supported, map them to a single quadword, quadword aligned.
     return CharUnits::fromQuantity(16);
   }