[codeview] Decode and dump FP regs from S_FRAMEPROC records

Summary:
There are two registers encoded in the S_FRAMEPROC flags: one for locals
and one for parameters. The encoding is described by the
ExpandEncodedBasePointerReg function in cvinfo.h. Two bits are used to
indicate one of four possible values:

  0: no register - Used when there are no variables.
  1: SP / standard - Variables are stored relative to the standard SP
     for the ISA.
  2: FP - Variables are addressed relative to the ISA frame
     pointer, i.e. EBP on x86. If realignment is required, parameters
     use this. If a dynamic alloca is used, locals will be EBP relative.
  3: Alternative - Variables are stored relative to some alternative
     third callee-saved register. This is required to address highly
     aligned locals when there are dynamic stack adjustments. In this
     case, both the incoming SP saved in the standard FP and the current
     SP are at some dynamic offset from the locals. LLVM uses ESI in
     this case, MSVC uses EBX.

Most of the changes in this patch are to pass around the CPU so that we
can decode these into real, named architectural registers.

Subscribers: hiraditya

Differential Revision: https://reviews.llvm.org/D51894

llvm-svn: 341999

1 files changed, 25 insertions, 6 deletions

diff --git a/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp b/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
index f8bf961f22a..4cb267e857e 100644
--- a/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
+++ b/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
@@ -32,8 +32,8 @@ namespace {
 class CVSymbolDumperImpl : public SymbolVisitorCallbacks {
 public:
   CVSymbolDumperImpl(TypeCollection &Types, SymbolDumpDelegate *ObjDelegate,
-                     ScopedPrinter &W, bool PrintRecordBytes)
-      : Types(Types), ObjDelegate(ObjDelegate), W(W),
+                     ScopedPrinter &W, CPUType CPU, bool PrintRecordBytes)
+      : Types(Types), ObjDelegate(ObjDelegate), W(W), CompilationCPUType(CPU),
         PrintRecordBytes(PrintRecordBytes), InFunctionScope(false) {}
 
 /// CVSymbolVisitor overrides.
@@ -46,6 +46,8 @@ public:
   Error visitSymbolEnd(CVSymbol &Record) override;
   Error visitUnknownSymbol(CVSymbol &Record) override;
 
+  CPUType getCompilationCPUType() const { return CompilationCPUType; }
+
 private:
   void printLocalVariableAddrRange(const LocalVariableAddrRange &Range,
                                    uint32_t RelocationOffset);
@@ -56,6 +58,9 @@ private:
   SymbolDumpDelegate *ObjDelegate;
   ScopedPrinter &W;
 
+  /// Save the machine or CPU type when dumping a compile symbols.
+  CPUType CompilationCPUType = CPUType::X64;
+
   bool PrintRecordBytes;
   bool InFunctionScope;
 };
@@ -235,6 +240,7 @@ Error CVSymbolDumperImpl::visitKnownRecord(CVSymbol &CVR,
   W.printEnum("Language", Compile2.getLanguage(), getSourceLanguageNames());
   W.printFlags("Flags", Compile2.getFlags(), getCompileSym2FlagNames());
   W.printEnum("Machine", unsigned(Compile2.Machine), getCPUTypeNames());
+  CompilationCPUType = Compile2.Machine;
   std::string FrontendVersion;
   {
     raw_string_ostream Out(FrontendVersion);
@@ -258,6 +264,7 @@ Error CVSymbolDumperImpl::visitKnownRecord(CVSymbol &CVR,
   W.printEnum("Language", Compile3.getLanguage(), getSourceLanguageNames());
   W.printFlags("Flags", Compile3.getFlags(), getCompileSym3FlagNames());
   W.printEnum("Machine", unsigned(Compile3.Machine), getCPUTypeNames());
+  CompilationCPUType = Compile3.Machine;
   std::string FrontendVersion;
   {
     raw_string_ostream Out(FrontendVersion);
@@ -415,6 +422,12 @@ Error CVSymbolDumperImpl::visitKnownRecord(CVSymbol &CVR,
              FrameProc.SectionIdOfExceptionHandler);
   W.printFlags("Flags", static_cast<uint32_t>(FrameProc.Flags),
                getFrameProcSymFlagNames());
+  W.printEnum("LocalFramePtrReg",
+              uint16_t(FrameProc.getLocalFramePtrReg(CompilationCPUType)),
+              getRegisterNames());
+  W.printEnum("ParamFramePtrReg",
+              uint16_t(FrameProc.getParamFramePtrReg(CompilationCPUType)),
+              getRegisterNames());
   return Error::success();
 }
 
@@ -625,21 +638,27 @@ Error CVSymbolDumperImpl::visitUnknownSymbol(CVSymbol &CVR) {
 Error CVSymbolDumper::dump(CVRecord<SymbolKind> &Record) {
   SymbolVisitorCallbackPipeline Pipeline;
   SymbolDeserializer Deserializer(ObjDelegate.get(), Container);
-  CVSymbolDumperImpl Dumper(Types, ObjDelegate.get(), W, PrintRecordBytes);
+  CVSymbolDumperImpl Dumper(Types, ObjDelegate.get(), W, CompilationCPUType,
+                            PrintRecordBytes);
 
   Pipeline.addCallbackToPipeline(Deserializer);
   Pipeline.addCallbackToPipeline(Dumper);
   CVSymbolVisitor Visitor(Pipeline);
-  return Visitor.visitSymbolRecord(Record);
+  auto Err = Visitor.visitSymbolRecord(Record);
+  CompilationCPUType = Dumper.getCompilationCPUType();
+  return Err;
 }
 
 Error CVSymbolDumper::dump(const CVSymbolArray &Symbols) {
   SymbolVisitorCallbackPipeline Pipeline;
   SymbolDeserializer Deserializer(ObjDelegate.get(), Container);
-  CVSymbolDumperImpl Dumper(Types, ObjDelegate.get(), W, PrintRecordBytes);
+  CVSymbolDumperImpl Dumper(Types, ObjDelegate.get(), W, CompilationCPUType,
+                            PrintRecordBytes);
 
   Pipeline.addCallbackToPipeline(Deserializer);
   Pipeline.addCallbackToPipeline(Dumper);
   CVSymbolVisitor Visitor(Pipeline);
-  return Visitor.visitSymbolStream(Symbols);
+  auto Err = Visitor.visitSymbolStream(Symbols);
+  CompilationCPUType = Dumper.getCompilationCPUType();
+  return Err;
 }