Generate native unwind info on Win64

This patch enables LLVM to emit Win64-native unwind info rather than
DWARF CFI.  It handles all corner cases (I hope), including stack
realignment.

Because the unwind info is not flexible enough to describe stack frames
with a gap of unknown size in the middle, such as the one caused by
stack realignment, I modified register spilling code to place all spills
into the fixed frame slots, so that they can be accessed relative to the
frame pointer.

Patch by Vadim Chugunov!

Reviewed By: rnk

Differential Revision: http://reviews.llvm.org/D4081

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211399 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 0 deletions

diff --git a/lib/Target/X86/X86MCInstLower.cpp b/lib/Target/X86/X86MCInstLower.cpp
index 0190080b93..3314c641c9 100644
--- a/lib/Target/X86/X86MCInstLower.cpp
+++ b/lib/Target/X86/X86MCInstLower.cpp
@@ -13,6 +13,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "X86AsmPrinter.h"
+#include "X86RegisterInfo.h"
 #include "InstPrinter/X86ATTInstPrinter.h"
 #include "MCTargetDesc/X86BaseInfo.h"
 #include "llvm/ADT/SmallString.h"
@@ -779,6 +780,9 @@ static void LowerPATCHPOINT(MCStreamer &OS, StackMaps &SM,
 
 void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
   X86MCInstLower MCInstLowering(*MF, *this);
+  const X86RegisterInfo *RI =
+      static_cast<const X86RegisterInfo *>(TM.getRegisterInfo());
+
   switch (MI->getOpcode()) {
   case TargetOpcode::DBG_VALUE:
     llvm_unreachable("Should be handled target independently");
@@ -883,6 +887,39 @@ void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
       .addReg(X86::R10)
       .addReg(X86::RAX));
     return;
+
+  case X86::SEH_PushReg:
+    OutStreamer.EmitWin64EHPushReg(
+        RI->getSEHRegNum(MI->getOperand(0).getImm()));
+    return;
+
+  case X86::SEH_SaveReg:
+    OutStreamer.EmitWin64EHSaveReg(RI->getSEHRegNum(MI->getOperand(0).getImm()),
+                                   MI->getOperand(1).getImm());
+    return;
+
+  case X86::SEH_SaveXMM:
+    OutStreamer.EmitWin64EHSaveXMM(RI->getSEHRegNum(MI->getOperand(0).getImm()),
+                                   MI->getOperand(1).getImm());
+    return;
+
+  case X86::SEH_StackAlloc:
+    OutStreamer.EmitWin64EHAllocStack(MI->getOperand(0).getImm());
+    return;
+
+  case X86::SEH_SetFrame:
+    OutStreamer.EmitWin64EHSetFrame(
+        RI->getSEHRegNum(MI->getOperand(0).getImm()),
+        MI->getOperand(1).getImm());
+    return;
+
+  case X86::SEH_PushFrame:
+    OutStreamer.EmitWin64EHPushFrame(MI->getOperand(0).getImm());
+    return;
+
+  case X86::SEH_EndPrologue:
+    OutStreamer.EmitWin64EHEndProlog();
+    return;
   }
 
   MCInst TmpInst;