Functions calling __builtin_eh_return must have a frame pointer.

The code in X86TargetLowering::LowerEH_RETURN() assumes that a frame
pointer exists, but the frame pointer was forced by the presence of
llvm.eh.unwind.init which isn't guaranteed.

If llvm.eh.unwind.init is actually required in functions calling
eh.return (is it?), we should diagnose that instead of emitting bad
machine code.

This should fix the dragonegg-x86_64-linux-gcc-4.6-test bot.

llvm-svn: 158961

2 files changed, 25 insertions, 4 deletions

diff --git a/llvm/lib/Target/X86/X86FrameLowering.cpp b/llvm/lib/Target/X86/X86FrameLowering.cpp
index c2b1cf7be2f..a65bc15b1e4 100644
--- a/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/llvm/lib/Target/X86/X86FrameLowering.cpp
@@ -52,7 +52,7 @@ bool X86FrameLowering::hasFP(const MachineFunction &MF) const {
           MFI->hasVarSizedObjects() ||
           MFI->isFrameAddressTaken() ||
           MF.getInfo<X86MachineFunctionInfo>()->getForceFramePointer() ||
-          MMI.callsUnwindInit());
+          MMI.callsUnwindInit() || MMI.callsEHReturn());
 }
 
 static unsigned getSUBriOpcode(unsigned is64Bit, int64_t Imm) {
diff --git a/llvm/test/CodeGen/X86/2008-08-31-EH_RETURN32.ll b/llvm/test/CodeGen/X86/2008-08-31-EH_RETURN32.ll
index 1d27fc53ea5..c63c890add5 100644
--- a/llvm/test/CodeGen/X86/2008-08-31-EH_RETURN32.ll
+++ b/llvm/test/CodeGen/X86/2008-08-31-EH_RETURN32.ll
@@ -1,15 +1,36 @@
 ; Check that eh_return & unwind_init were properly lowered
-; RUN: llc < %s | grep %ebp | count 9
-; RUN: llc < %s | grep %ecx | count 5
+; RUN: llc < %s -verify-machineinstrs | FileCheck %s
 
 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64"
 target triple = "i386-pc-linux"
 
-define i8* @test(i32 %a, i8* %b)  {
+; CHECK: test1
+; CHECK: pushl %ebp
+define i8* @test1(i32 %a, i8* %b)  {
 entry:
   call void @llvm.eh.unwind.init()
   %foo   = alloca i32
   call void @llvm.eh.return.i32(i32 %a, i8* %b)
+; CHECK: movl 12(%ebp), %[[ECX:e..]]
+; CHECK: movl 8(%ebp), %[[EAX:e..]]
+; CHECK: movl %[[ECX]], 4(%ebp,%[[EAX]])
+; CHECK: leal 4(%ebp,%[[EAX]]), %[[ECX2:e..]]
+; CHECK: movl %[[ECX2]], %esp
+; CHECK: ret
+  unreachable
+}
+
+; CHECK: test2
+; CHECK: pushl %ebp
+define i8* @test2(i32 %a, i8* %b)  {
+entry:
+  call void @llvm.eh.return.i32(i32 %a, i8* %b)
+; CHECK: movl 12(%ebp), %[[ECX:e..]]
+; CHECK: movl 8(%ebp), %[[EAX:e..]]
+; CHECK: movl %[[ECX]], 4(%ebp,%[[EAX]])
+; CHECK: leal 4(%ebp,%[[EAX]]), %[[ECX2:e..]]
+; CHECK: movl %[[ECX2]], %esp
+; CHECK: ret
   unreachable
 }