Remove code that pad number of bytes to pop for X86_FastCall CC. The code doesn't do the "aligning" for Cygwin, Mingw, and Windows. But aligning it on Darwin and Linux breaks gcc compatibility. That ruled out all the platforms we support!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55756 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 1 insertions, 16 deletions

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 9b492fb..cd01c64 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1379,14 +1379,6 @@ X86TargetLowering::LowerFORMAL_ARGUMENTS(SDValue Op, SelectionDAG &DAG) {
     }
   }
   
-  // Make sure the instruction takes 8n+4 bytes to make sure the start of the
-  // arguments and the arguments after the retaddr has been pushed are
-  // aligned.
-  if (!Is64Bit && CC == CallingConv::X86_FastCall &&
-      !Subtarget->isTargetCygMing() && !Subtarget->isTargetWindows() &&
-      (StackSize & 7) == 0)
-    StackSize += 4;
-
   ArgValues.push_back(Root);
 
   // Some CCs need callee pop.
@@ -1494,13 +1486,6 @@ SDValue X86TargetLowering::LowerCALL(SDValue Op, SelectionDAG &DAG) {
   if (CC == CallingConv::Fast)
     NumBytes = GetAlignedArgumentStackSize(NumBytes, DAG);
 
-  // Make sure the instruction takes 8n+4 bytes to make sure the start of the
-  // arguments and the arguments after the retaddr has been pushed are aligned.
-  if (!Is64Bit && CC == CallingConv::X86_FastCall &&
-      !Subtarget->isTargetCygMing() && !Subtarget->isTargetWindows() &&
-      (NumBytes & 7) == 0)
-    NumBytes += 4;
-
   int FPDiff = 0;
   if (IsTailCall) {
     // Lower arguments at fp - stackoffset + fpdiff.
diff --git a/test/CodeGen/X86/fast-cc-callee-pops.ll b/test/CodeGen/X86/fast-cc-callee-pops.ll
index 9b03634..941f708 100644
--- a/test/CodeGen/X86/fast-cc-callee-pops.ll
+++ b/test/CodeGen/X86/fast-cc-callee-pops.ll
@@ -3,6 +3,6 @@
 
 ; Check that a fastcc function pops its stack variables before returning.
 
-define x86_fastcallcc void @func(i64 %X, i64 %Y, float %G, double %Z) {
+define x86_fastcallcc void @func(i64 %X, i64 %Y, float %G, double %Z) nounwind {
         ret void
 }