Fix wrong code offset for unwind code SET_FPREG.

The code offset for unwind code SET_FPREG is wrong because it is set
to constant 0. The fix is to do the same as for the other unwind
codes: emit a label and later the absolute difference between the
label and the begin of the prologue.
Also enables the failing test case MC/COFF/seh.s

Reviewed by Jim Grosbach, Charles Davis and Nico Rieck.

llvm-svn: 189309

4 files changed, 6 insertions, 7 deletions

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 6542f42a03b..fb43a4adbda 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -470,7 +470,9 @@ void MCStreamer::EmitWin64EHSetFrame(unsigned Register, unsigned Offset) {
     report_fatal_error("Frame register and offset already specified!");
   if (Offset & 0x0F)
     report_fatal_error("Misaligned frame pointer offset!");
-  MCWin64EHInstruction Inst(Win64EH::UOP_SetFPReg, 0, Register, Offset);
+  MCSymbol *Label = getContext().CreateTempSymbol();
+  MCWin64EHInstruction Inst(Win64EH::UOP_SetFPReg, Label, Register, Offset);
+  EmitLabel(Label);
   CurFrame->LastFrameInst = CurFrame->Instructions.size();
   CurFrame->Instructions.push_back(Inst);
 }
diff --git a/llvm/lib/MC/MCWin64EH.cpp b/llvm/lib/MC/MCWin64EH.cpp
index c5b637c9244..8db1fa2a93c 100644
--- a/llvm/lib/MC/MCWin64EH.cpp
+++ b/llvm/lib/MC/MCWin64EH.cpp
@@ -64,7 +64,7 @@ static void EmitAbsDifference(MCStreamer &streamer, MCSymbol *lhs,
 
 static void EmitUnwindCode(MCStreamer &streamer, MCSymbol *begin,
                            MCWin64EHInstruction &inst) {
-  uint8_t b1, b2;
+  uint8_t b2;
   uint16_t w;
   b2 = (inst.getOperation() & 0x0F);
   switch (inst.getOperation()) {
@@ -93,8 +93,7 @@ static void EmitUnwindCode(MCStreamer &streamer, MCSymbol *begin,
     streamer.EmitIntValue(b2, 1);
     break;
   case Win64EH::UOP_SetFPReg:
-    b1 = inst.getOffset() & 0xF0;
-    streamer.EmitIntValue(b1, 1);
+    EmitAbsDifference(streamer, inst.getLabel(), begin);
     streamer.EmitIntValue(b2, 1);
     break;
   case Win64EH::UOP_SaveNonVol:
diff --git a/llvm/test/MC/COFF/seh.s b/llvm/test/MC/COFF/seh.s
index bef425efb43..b1e61a97739 100644
--- a/llvm/test/MC/COFF/seh.s
+++ b/llvm/test/MC/COFF/seh.s
@@ -1,7 +1,5 @@
 // This test checks that the SEH directives emit the correct unwind data.
 
-// TODO: Expected fail because SET_FPREG has a wrong offset.
-// XFAIL: *
 // RUN: llvm-mc -triple x86_64-pc-win32 -filetype=obj %s | llvm-readobj -s -u | FileCheck %s
 
 // CHECK:      Sections [
diff --git a/llvm/test/tools/llvm-objdump/win64-unwind-data.s b/llvm/test/tools/llvm-objdump/win64-unwind-data.s
index 1e4c7428ce3..a172bfca6b3 100644
--- a/llvm/test/tools/llvm-objdump/win64-unwind-data.s
+++ b/llvm/test/tools/llvm-objdump/win64-unwind-data.s
@@ -13,7 +13,7 @@
 // CHECK-NEXT: Frame register: RBX
 // CHECK-NEXT: Frame offset: 0
 // CHECK-NEXT: Unwind Codes:
-// CHECK-NEXT: 0x00: UOP_SetFPReg
+// CHECK-NEXT: 0x12: UOP_SetFPReg
 // CHECK-NEXT: 0x0f: UOP_PushNonVol RBX
 // CHECK-NEXT: 0x0e: UOP_SaveXMM128 XMM8 [0x0000]
 // CHECK-NEXT: 0x09: UOP_SaveNonVol RSI [0x0010]