Test .seh_startchained and .seh_endchained parsing.

Rework how the MCWin64EHUnwindInfo instances are stored. Fix issues with
chained unwind areas exposed by the test that were related to this.

The ChainedParent field had the wrong address, because when the chained unwind
info was added, the addresses shifted around. Now we store the pointers to the
structures, which are now allocated from the MC heap.

llvm-svn: 132106

3 files changed, 18 insertions, 15 deletions

diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index 9dd8d4b5335..c05a9251dc7 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -58,7 +58,7 @@ namespace llvm {
     MCDwarfFrameInfo *getCurrentFrameInfo();
     void EnsureValidFrame();
 
-    std::vector<MCWin64EHUnwindInfo> W64UnwindInfos;
+    std::vector<MCWin64EHUnwindInfo *> W64UnwindInfos;
     MCWin64EHUnwindInfo *CurrentW64UnwindInfo;
     void setCurrentW64UnwindInfo(MCWin64EHUnwindInfo *Frame);
     void EnsureValidW64UnwindInfo();
@@ -101,7 +101,7 @@ namespace llvm {
     }
 
     MCWin64EHUnwindInfo &getW64UnwindInfo(unsigned i) {
-      return W64UnwindInfos[i];
+      return *W64UnwindInfos[i];
     }
 
     /// @name Assembly File Formatting.
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 19aeaafc722..9957a76ba38 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -307,8 +307,8 @@ void MCStreamer::EmitCFISameValue(int64_t Register) {
 }
 
 void MCStreamer::setCurrentW64UnwindInfo(MCWin64EHUnwindInfo *Frame) {
-  W64UnwindInfos.push_back(*Frame);
-  CurrentW64UnwindInfo = &W64UnwindInfos.back();
+  W64UnwindInfos.push_back(Frame);
+  CurrentW64UnwindInfo = W64UnwindInfos.back();
 }
 
 void MCStreamer::EnsureValidW64UnwindInfo() {
@@ -321,11 +321,11 @@ void MCStreamer::EmitWin64EHStartProc(const MCSymbol *Symbol) {
   MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
   if (CurFrame && !CurFrame->End)
     report_fatal_error("Starting a function before ending the previous one!");
-  MCWin64EHUnwindInfo Frame;
-  Frame.Begin = getContext().CreateTempSymbol();
-  Frame.Function = Symbol;
-  EmitLabel(Frame.Begin);
-  setCurrentW64UnwindInfo(&Frame);
+  MCWin64EHUnwindInfo *Frame = new (getContext()) MCWin64EHUnwindInfo;
+  Frame->Begin = getContext().CreateTempSymbol();
+  Frame->Function = Symbol;
+  EmitLabel(Frame->Begin);
+  setCurrentW64UnwindInfo(Frame);
 }
 
 void MCStreamer::EmitWin64EHEndProc() {
@@ -339,13 +339,13 @@ void MCStreamer::EmitWin64EHEndProc() {
 
 void MCStreamer::EmitWin64EHStartChained() {
   EnsureValidW64UnwindInfo();
-  MCWin64EHUnwindInfo Frame;
+  MCWin64EHUnwindInfo *Frame = new (getContext()) MCWin64EHUnwindInfo;
   MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
-  Frame.Begin = getContext().CreateTempSymbol();
-  Frame.Function = CurFrame->Function;
-  Frame.ChainedParent = CurFrame;
-  EmitLabel(Frame.Begin);
-  setCurrentW64UnwindInfo(&Frame);
+  Frame->Begin = getContext().CreateTempSymbol();
+  Frame->Function = CurFrame->Function;
+  Frame->ChainedParent = CurFrame;
+  EmitLabel(Frame->Begin);
+  setCurrentW64UnwindInfo(Frame);
 }
 
 void MCStreamer::EmitWin64EHEndChained() {
diff --git a/llvm/test/MC/AsmParser/directive_seh.s b/llvm/test/MC/AsmParser/directive_seh.s
index d4f7625e885..b4384daf481 100644
--- a/llvm/test/MC/AsmParser/directive_seh.s
+++ b/llvm/test/MC/AsmParser/directive_seh.s
@@ -35,6 +35,9 @@ func:
     .seh_handlerdata
     .long 0
     .text
+    .seh_startchained
+    .seh_endprologue
+    .seh_endchained
     lea (%rbx), %rsp
     pop %rbx
     addq $24, %rsp