[llvm-commits] [llvm] r148513 - in /llvm/trunk: lib/Target/X86/X86FastISel.cpp lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/win32_sret.ll

[Eli Friedman]

Author: efriedma
Date: Thu Jan 19 18:05:46 2012
New Revision: 148513

URL: http://llvm.org/viewvc/llvm-project?rev=148513&view=rev
Log:
Support MSVC x86-32 sret convention.  PR11688.  Patch by Joe Groff.


Added:
    llvm/trunk/test/CodeGen/X86/win32_sret.ll
Modified:
    llvm/trunk/lib/Target/X86/X86FastISel.cpp
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

Modified: llvm/trunk/lib/Target/X86/X86FastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FastISel.cpp?rev=148513&r1=148512&r2=148513&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FastISel.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FastISel.cpp Thu Jan 19 18:05:46 2012
@@ -1855,7 +1855,8 @@
   // Issue CALLSEQ_END
   unsigned AdjStackUp = TII.getCallFrameDestroyOpcode();
   unsigned NumBytesCallee = 0;
-  if (!Subtarget->is64Bit() && CS.paramHasAttr(1, Attribute::StructRet))
+  if (!Subtarget->is64Bit() && !Subtarget->isTargetWindows() &&
+      CS.paramHasAttr(1, Attribute::StructRet))
     NumBytesCallee = 4;
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(AdjStackUp))
     .addImm(NumBytes).addImm(NumBytesCallee);

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=148513&r1=148512&r2=148513&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Thu Jan 19 18:05:46 2012
@@ -1811,6 +1811,7 @@
 
   MachineFrameInfo *MFI = MF.getFrameInfo();
   bool Is64Bit = Subtarget->is64Bit();
+  bool IsWindows = Subtarget->isTargetWindows();
   bool IsWin64 = Subtarget->isTargetWin64();
 
   assert(!(isVarArg && IsTailCallConvention(CallConv)) &&
@@ -2046,7 +2047,8 @@
   } else {
     FuncInfo->setBytesToPopOnReturn(0); // Callee pops nothing.
     // If this is an sret function, the return should pop the hidden pointer.
-    if (!Is64Bit && !IsTailCallConvention(CallConv) && ArgsAreStructReturn(Ins))
+    if (!Is64Bit && !IsTailCallConvention(CallConv) && !IsWindows &&
+        ArgsAreStructReturn(Ins))
       FuncInfo->setBytesToPopOnReturn(4);
   }
 
@@ -2130,6 +2132,7 @@
   MachineFunction &MF = DAG.getMachineFunction();
   bool Is64Bit        = Subtarget->is64Bit();
   bool IsWin64        = Subtarget->isTargetWin64();
+  bool IsWindows      = Subtarget->isTargetWindows();
   bool IsStructRet    = CallIsStructReturn(Outs);
   bool IsSibcall      = false;
 
@@ -2543,10 +2546,12 @@
   if (X86::isCalleePop(CallConv, Is64Bit, isVarArg,
                        getTargetMachine().Options.GuaranteedTailCallOpt))
     NumBytesForCalleeToPush = NumBytes;    // Callee pops everything
-  else if (!Is64Bit && !IsTailCallConvention(CallConv) && IsStructRet)
+  else if (!Is64Bit && !IsTailCallConvention(CallConv) && !IsWindows &&
+           IsStructRet)
     // If this is a call to a struct-return function, the callee
     // pops the hidden struct pointer, so we have to push it back.
     // This is common for Darwin/X86, Linux & Mingw32 targets.
+    // For MSVC Win32 targets, the caller pops the hidden struct pointer.
     NumBytesForCalleeToPush = 4;
   else
     NumBytesForCalleeToPush = 0;  // Callee pops nothing.

Added: llvm/trunk/test/CodeGen/X86/win32_sret.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/win32_sret.ll?rev=148513&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/win32_sret.ll (added)
+++ llvm/trunk/test/CodeGen/X86/win32_sret.ll Thu Jan 19 18:05:46 2012
@@ -0,0 +1,28 @@
+; RUN: llc < %s -mtriple=i686-pc-win32 | FileCheck %s -check-prefix=WIN_X32
+; RUN: llc < %s -mtriple=i686-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X32
+; RUN: llc < %s -mtriple=i386-pc-linux | FileCheck %s -check-prefix=LINUX
+; RUN: llc < %s -O0 -mtriple=i686-pc-win32 | FileCheck %s -check-prefix=WIN_X32
+; RUN: llc < %s -O0 -mtriple=i686-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X32
+; RUN: llc < %s -O0 -mtriple=i386-pc-linux | FileCheck %s -check-prefix=LINUX
+
+; The SysV ABI used by most Unixes and Mingw on x86 specifies that an sret pointer
+; is callee-cleanup. However, in MSVC's cdecl calling convention, sret pointer
+; arguments are caller-cleanup like normal arguments.
+
+define void @sret1(i8* sret) nounwind {
+entry:
+; WIN_X32:    {{ret$}}
+; MINGW_X32:  ret $4
+; LINUX:      ret $4
+  ret void
+}
+
+define void @sret2(i32* sret %x, i32 %y) nounwind {
+entry:
+; WIN_X32:    {{ret$}}
+; MINGW_X32:  ret $4
+; LINUX:      ret $4
+  store i32 %y, i32* %x
+  ret void
+}
+