[AArch64] Produce the right kind of va_arg for windows

On windows on arm64, the va_list is a plain pointer.

Differential Revision: https://reviews.llvm.org/D35008

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@307933 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 3 deletions

diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index eeebd60a2d..c17828974e 100644
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -4785,7 +4785,8 @@ class AArch64ABIInfo : public SwiftABIInfo {
 public:
   enum ABIKind {
     AAPCS = 0,
-    DarwinPCS
+    DarwinPCS,
+    Win64
   };
 
 private:
@@ -4823,10 +4824,14 @@ private:
 
   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
                     QualType Ty) const override {
-    return isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
-                         : EmitAAPCSVAArg(VAListAddr, Ty, CGF);
+    return Kind == Win64 ? EmitMSVAArg(CGF, VAListAddr, Ty)
+                         : isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
+                                         : EmitAAPCSVAArg(VAListAddr, Ty, CGF);
   }
 
+  Address EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
+                      QualType Ty) const override;
+
   bool shouldPassIndirectlyForSwift(CharUnits totalSize,
                                     ArrayRef<llvm::Type*> scalars,
                                     bool asReturnValue) const override {
@@ -5332,6 +5337,14 @@ Address AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
                           TyInfo, SlotSize, /*AllowHigherAlign*/ true);
 }
 
+Address AArch64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
+                                    QualType Ty) const {
+  return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
+                          CGF.getContext().getTypeInfoInChars(Ty),
+                          CharUnits::fromQuantity(8),
+                          /*allowHigherAlign*/ false);
+}
+
 //===----------------------------------------------------------------------===//
 // ARM ABI Implementation
 //===----------------------------------------------------------------------===//
@@ -8494,6 +8507,8 @@ const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
     AArch64ABIInfo::ABIKind Kind = AArch64ABIInfo::AAPCS;
     if (getTarget().getABI() == "darwinpcs")
       Kind = AArch64ABIInfo::DarwinPCS;
+    else if (Triple.isOSWindows())
+      Kind = AArch64ABIInfo::Win64;
 
     return SetCGInfo(new AArch64TargetCodeGenInfo(Types, Kind));
   }