[codeview] Improve readability of type record assembly

Adds the method MCStreamer::EmitBinaryData, which is usually an alias
for EmitBytes. In the MCAsmStreamer case, it is overridden to emit hex
dump output like this:
        .byte   0x0e, 0x00, 0x08, 0x10
        .byte   0x03, 0x00, 0x00, 0x00
        .byte   0x00, 0x00, 0x00, 0x00
        .byte   0x00, 0x10, 0x00, 0x00

Also, when verbose asm comments are enabled, this patch prints the dump
output for each comment before its record, like this:
        # ArgList (0x1000) {
        #   TypeLeafKind: LF_ARGLIST (0x1201)
        #   NumArgs: 0
        #   Arguments [
        #   ]
        # }
        .byte   0x06, 0x00, 0x01, 0x12
        .byte   0x00, 0x00, 0x00, 0x00

This should make debugging easier and testing more convenient.

Reviewers: aaboud

Subscribers: majnemer, zturner, amccarth, aaboud, llvm-commits

Differential Revision: http://reviews.llvm.org/D20711

llvm-svn: 271313

2 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index 5fbecb408f3..c85ffd5182d 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -162,6 +162,8 @@ public:
   void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
                       unsigned ByteAlignment = 0) override;
 
+  void EmitBinaryData(StringRef Data) override;
+
   void EmitBytes(StringRef Data) override;
 
   void EmitValueImpl(const MCExpr *Value, unsigned Size,
@@ -709,6 +711,20 @@ void MCAsmStreamer::EmitBytes(StringRef Data) {
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitBinaryData(StringRef Data) {
+  // This is binary data. Print it in a grid of hex bytes for readability.
+  const size_t Cols = 4;
+  for (size_t I = 0, EI = alignTo(Data.size(), Cols); I < EI; I += Cols) {
+    size_t J = I, EJ = std::min(I + Cols, Data.size());
+    assert(EJ > 0);
+    OS << MAI->getData8bitsDirective();
+    for (; J < EJ - 1; ++J)
+      OS << format("0x%02x", uint8_t(Data[J])) << ", ";
+    OS << format("0x%02x", uint8_t(Data[J]));
+    EmitEOL();
+  }
+}
+
 void MCAsmStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
   EmitValue(MCConstantExpr::create(Value, getContext()), Size);
 }
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 9ed5a5faacd..8872d321d88 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -761,6 +761,7 @@ void MCStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
 void MCStreamer::ChangeSection(MCSection *, const MCExpr *) {}
 void MCStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
 void MCStreamer::EmitBytes(StringRef Data) {}
+void MCStreamer::EmitBinaryData(StringRef Data) { EmitBytes(Data); }
 void MCStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) {
   visitUsedExpr(*Value);
 }