Add basic support for .cfi_personality.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122566 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 91 insertions, 21 deletions

diff --git a/include/llvm/MC/MCStreamer.h b/include/llvm/MC/MCStreamer.h
index b85ea3fae1..e6da43ba20 100644
--- a/include/llvm/MC/MCStreamer.h
+++ b/include/llvm/MC/MCStreamer.h
@@ -52,6 +52,10 @@ namespace llvm {
     void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
                          bool isPCRel, unsigned AddrSpace);
 
+    std::vector<MCDwarfFrameInfo> FrameInfos;
+    MCDwarfFrameInfo *getCurrentFrameInfo();
+    void EnsureValidFrame();
+
   protected:
     MCStreamer(MCContext &Ctx);
 
@@ -63,10 +67,6 @@ namespace llvm {
     /// is kept up to date by SwitchSection.
     const MCSection *PrevSection;
 
-    std::vector<MCDwarfFrameInfo> FrameInfos;
-    MCDwarfFrameInfo *getCurrentFrameInfo();
-    void EnsureValidFrame();
-
   public:
     virtual ~MCStreamer();
 
diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 24ddc82563..a4d34f386a 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -475,8 +475,8 @@ static void EmitFrameMoves(MCStreamer &streamer,
         streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_offset, 1);
       } else {
         streamer.EmitIntValue(dwarf::DW_CFA_def_cfa, 1);
-        streamer.EmitULEB128IntValue(asmInfo.getDwarfRegNum(Src.getReg(), isEH),
-                                     1);
+        streamer.EmitULEB128IntValue(asmInfo.getDwarfRegNum(Src.getReg(),
+                                                            isEH));
       }
 
       streamer.EmitULEB128IntValue(-Src.getOffset(), 1);
@@ -508,7 +508,8 @@ static void EmitFrameMoves(MCStreamer &streamer,
   }
 }
 
-static const MCSymbol &EmitCIE(MCStreamer &streamer) {
+static const MCSymbol &EmitCIE(MCStreamer &streamer,
+                               const MCSymbol *personality) {
   MCContext &context = streamer.getContext();
   const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
   const MCSection &section = *asmInfo.getEHFrameSection();
@@ -530,7 +531,10 @@ static const MCSymbol &EmitCIE(MCStreamer &streamer) {
 
   // Augmentation String
   SmallString<8> Augmentation;
-  Augmentation += "zR";
+  Augmentation += "z";
+  if (personality)
+    Augmentation += "P";
+  Augmentation += "R";
   streamer.EmitBytes(Augmentation.str(), 0);
   streamer.EmitIntValue(0, 1);
 
@@ -553,6 +557,13 @@ static const MCSymbol &EmitCIE(MCStreamer &streamer) {
 
   // Augmentation Data (optional)
   streamer.EmitLabel(augmentationStart);
+  if (personality) {
+    // Personality Encoding
+    streamer.EmitIntValue(dwarf::DW_EH_PE_absptr, 1);
+    // Personality
+    streamer.EmitSymbolValue(personality, 8);
+  }
+  // Encoding of the FDE pointers
   streamer.EmitIntValue(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4, 1);
   streamer.EmitLabel(augmentationEnd);
 
@@ -563,7 +574,7 @@ static const MCSymbol &EmitCIE(MCStreamer &streamer) {
   EmitFrameMoves(streamer, Moves, NULL, true);
 
   // Padding
-  streamer.EmitValueToAlignment(asmInfo.getPointerSize());
+  streamer.EmitValueToAlignment(4);
 
   streamer.EmitLabel(sectionEnd);
   return *sectionStart;
@@ -608,13 +619,19 @@ static MCSymbol *EmitFDE(MCStreamer &streamer,
 void MCDwarfFrameEmitter::Emit(MCStreamer &streamer) {
   const MCContext &context = streamer.getContext();
   const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
-  const MCSymbol &cieStart = EmitCIE(streamer);
   MCSymbol *fdeEnd = NULL;
+  DenseMap<const MCSymbol*, const MCSymbol*> Personalities;
+
   for (unsigned i = 0, n = streamer.getNumFrameInfos(); i < n; ++i) {
-    fdeEnd = EmitFDE(streamer, cieStart, streamer.getFrameInfo(i));
+    const MCDwarfFrameInfo &frame = streamer.getFrameInfo(i);
+    const MCSymbol *&cieStart = Personalities[frame.Personality];
+    if (!cieStart)
+      cieStart = &EmitCIE(streamer, frame.Personality);
+    fdeEnd = EmitFDE(streamer, *cieStart, frame);
     if (i != n - 1)
       streamer.EmitLabel(fdeEnd);
   }
+
   streamer.EmitValueToAlignment(asmInfo.getPointerSize());
   if (fdeEnd)
     streamer.EmitLabel(fdeEnd);
diff --git a/lib/MC/MCELFStreamer.cpp b/lib/MC/MCELFStreamer.cpp
index 4636e2a1f0..2369821204 100644
--- a/lib/MC/MCELFStreamer.cpp
+++ b/lib/MC/MCELFStreamer.cpp
@@ -488,7 +488,7 @@ void MCELFStreamer::EmitInstToData(const MCInst &Inst) {
 }
 
 void MCELFStreamer::Finish() {
-  if (!FrameInfos.empty())
+  if (getNumFrameInfos())
     MCDwarfFrameEmitter::Emit(*this);
 
   for (std::vector<LocalCommon>::const_iterator i = LocalCommons.begin(),
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index aac5535155..cf11ca9c5a 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -2206,6 +2206,29 @@ bool GenericAsmParser::ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc) {
   return getStreamer().EmitCFIOffset(Register, Offset);
 }
 
+static bool isValidEncoding(int64_t Encoding) {
+  if (Encoding & ~0xff)
+    return false;
+
+  if (Encoding == dwarf::DW_EH_PE_omit)
+    return true;
+
+  const unsigned Format = Encoding & 0xf;
+  if (Format != dwarf::DW_EH_PE_absptr && Format != dwarf::DW_EH_PE_udata2 &&
+      Format != dwarf::DW_EH_PE_udata4 && Format != dwarf::DW_EH_PE_udata8 &&
+      Format != dwarf::DW_EH_PE_sdata2 && Format != dwarf::DW_EH_PE_sdata4 &&
+      Format != dwarf::DW_EH_PE_sdata8 && Format != dwarf::DW_EH_PE_signed)
+    return false;
+
+  const unsigned Application = Encoding & 0xf0;
+  if (Application != dwarf::DW_EH_PE_absptr &&
+      Application != dwarf::DW_EH_PE_pcrel &&
+      Application != dwarf::DW_EH_PE_indirect)
+    return false;
+
+  return true;
+}
+
 /// ParseDirectiveCFIPersonalityOrLsda
 /// ::= .cfi_personality encoding, [symbol_name]
 /// ::= .cfi_lsda encoding, [symbol_name]
@@ -2214,10 +2237,10 @@ bool GenericAsmParser::ParseDirectiveCFIPersonalityOrLsda(StringRef IDVal,
   int64_t Encoding = 0;
   if (getParser().ParseAbsoluteExpression(Encoding))
     return true;
-  if (Encoding == 255)
+  if (Encoding == dwarf::DW_EH_PE_omit)
     return false;
 
-  if (Encoding != 0)
+  if (!isValidEncoding(Encoding))
     return TokError("unsupported encoding.");
 
   if (getLexer().isNot(AsmToken::Comma))
diff --git a/test/MC/ELF/cfi.s b/test/MC/ELF/cfi.s
index 5657925ce5..3075e43d8b 100644
--- a/test/MC/ELF/cfi.s
+++ b/test/MC/ELF/cfi.s
@@ -7,6 +7,18 @@ f1:
 
 f2:
         .cfi_startproc
+        .cfi_personality 0x00, foo
+        nop
+        .cfi_endproc
+
+f3:
+        .cfi_startproc
+        nop
+        .cfi_endproc
+
+f4:
+        .cfi_startproc
+        .cfi_personality 0x00, foo
         nop
         .cfi_endproc
 
@@ -16,12 +28,12 @@ f2:
 // CHECK-NEXT:  ('sh_flags', 0x00000002)
 // CHECK-NEXT:  ('sh_addr', 0x00000000)
 // CHECK-NEXT:  ('sh_offset', 0x00000048)
-// CHECK-NEXT:  ('sh_size', 0x00000040)
+// CHECK-NEXT:  ('sh_size', 0x00000088)
 // CHECK-NEXT:  ('sh_link', 0x00000000)
 // CHECK-NEXT:  ('sh_info', 0x00000000)
 // CHECK-NEXT:  ('sh_addralign', 0x00000008)
 // CHECK-NEXT:  ('sh_entsize', 0x00000000)
-// CHECK-NEXT:  ('_section_data', '14000000 00000000 017a5200 01781001 1b0c0708 90010000 10000000 1c000000 00000000 01000000 00000000 10000000 30000000 00000000 01000000 00000000')
+// CHECK-NEXT:  ('_section_data', '14000000 00000000 017a5200 01781001 1b0c0708 90010000 10000000 1c000000 00000000 01000000 00000000 1c000000 00000000 017a5052 00017810 0a000000 00000000 00001b0c 07089001 10000000 24000000 00000000 01000000 00000000 10000000 64000000 00000000 01000000 00000000 10000000 4c000000 00000000 01000000 00000000')
 // CHECK-NEXT: ),
 
 // CHECK:      # Section 0x00000008
@@ -29,8 +41,8 @@ f2:
 // CHECK-NEXT:  ('sh_type', 0x00000004)
 // CHECK-NEXT:  ('sh_flags', 0x00000000)
 // CHECK-NEXT:  ('sh_addr', 0x00000000)
-// CHECK-NEXT:  ('sh_offset', 0x00000180)
-// CHECK-NEXT:  ('sh_size', 0x00000030)
+// CHECK-NEXT:  ('sh_offset', 0x00000220)
+// CHECK-NEXT:  ('sh_size', 0x00000078)
 // CHECK-NEXT:  ('sh_link', 0x00000006)
 // CHECK-NEXT:  ('sh_info', 0x00000004)
 // CHECK-NEXT:  ('sh_addralign', 0x00000008)
@@ -38,15 +50,33 @@ f2:
 // CHECK-NEXT:  ('_relocations', [
 // CHECK-NEXT:   # Relocation 0x00000000
 // CHECK-NEXT:   (('r_offset', 0x00000020)
-// CHECK-NEXT:    ('r_sym', 0x00000003)
+// CHECK-NEXT:    ('r_sym', 0x00000005)
 // CHECK-NEXT:    ('r_type', 0x00000002)
 // CHECK-NEXT:    ('r_addend', 0x00000000)
 // CHECK-NEXT:   ),
 // CHECK-NEXT:   # Relocation 0x00000001
-// CHECK-NEXT:   (('r_offset', 0x00000034)
-// CHECK-NEXT:    ('r_sym', 0x00000003)
+// CHECK-NEXT:   (('r_offset', 0x0000003e)
+// CHECK-NEXT:    ('r_sym', 0x00000009)
+// CHECK-NEXT:    ('r_type', 0x00000001)
+// CHECK-NEXT:    ('r_addend', 0x00000000)
+// CHECK-NEXT:   ),
+// CHECK-NEXT:   # Relocation 0x00000002
+// CHECK-NEXT:   (('r_offset', 0x00000054)
+// CHECK-NEXT:    ('r_sym', 0x00000005)
 // CHECK-NEXT:    ('r_type', 0x00000002)
 // CHECK-NEXT:    ('r_addend', 0x00000001)
 // CHECK-NEXT:   ),
+// CHECK-NEXT:   # Relocation 0x00000003
+// CHECK-NEXT:   (('r_offset', 0x00000068)
+// CHECK-NEXT:    ('r_sym', 0x00000005)
+// CHECK-NEXT:    ('r_type', 0x00000002)
+// CHECK-NEXT:    ('r_addend', 0x00000002)
+// CHECK-NEXT:   ),
+// CHECK-NEXT:   # Relocation 0x00000004
+// CHECK-NEXT:   (('r_offset', 0x0000007c)
+// CHECK-NEXT:    ('r_sym', 0x00000005)
+// CHECK-NEXT:    ('r_type', 0x00000002)
+// CHECK-NEXT:    ('r_addend', 0x00000003)
+// CHECK-NEXT:   ),
 // CHECK-NEXT:  ])
 // CHECK-NEXT: ),