ARM IAS: support .personalityindex

The .personalityindex directive is equivalent to the .personality directive with
the ARM EABI personality with the specific index (0, 1, 2).  Both of these
directives indicate personality routines, so enhance the personality directive
handling to take into account personalityindex.

Bonus fix: flush the UnwindContext at the beginning of a new function.

Thanks to Logan Chien for additional tests!

llvm-svn: 199706

3 files changed, 109 insertions, 7 deletions

diff --git a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 1a3df51acd9..0a1ba9105a7 100644
--- a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -40,6 +40,7 @@
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/MC/MCTargetAsmParser.h"
 #include "llvm/Support/ARMBuildAttributes.h"
+#include "llvm/Support/ARMEHABI.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ELF.h"
 #include "llvm/Support/MathExtras.h"
@@ -121,6 +122,7 @@ class UnwindContext {
   Locs FnStartLocs;
   Locs CantUnwindLocs;
   Locs PersonalityLocs;
+  Locs PersonalityIndexLocs;
   Locs HandlerDataLocs;
   int FPReg;
 
@@ -130,12 +132,15 @@ public:
   bool hasFnStart() const { return !FnStartLocs.empty(); }
   bool cantUnwind() const { return !CantUnwindLocs.empty(); }
   bool hasHandlerData() const { return !HandlerDataLocs.empty(); }
-  bool hasPersonality() const { return !PersonalityLocs.empty(); }
+  bool hasPersonality() const {
+    return !(PersonalityLocs.empty() && PersonalityIndexLocs.empty());
+  }
 
   void recordFnStart(SMLoc L) { FnStartLocs.push_back(L); }
   void recordCantUnwind(SMLoc L) { CantUnwindLocs.push_back(L); }
   void recordPersonality(SMLoc L) { PersonalityLocs.push_back(L); }
   void recordHandlerData(SMLoc L) { HandlerDataLocs.push_back(L); }
+  void recordPersonalityIndex(SMLoc L) { PersonalityIndexLocs.push_back(L); }
 
   void saveFPReg(int Reg) { FPReg = Reg; }
   int getFPReg() const { return FPReg; }
@@ -157,8 +162,18 @@ public:
   }
   void emitPersonalityLocNotes() const {
     for (Locs::const_iterator PI = PersonalityLocs.begin(),
-                              PE = PersonalityLocs.end(); PI != PE; ++PI)
-      Parser.Note(*PI, ".personality was specified here");
+                              PE = PersonalityLocs.end(),
+                              PII = PersonalityIndexLocs.begin(),
+                              PIE = PersonalityIndexLocs.end();
+         PI != PE || PII != PIE;) {
+      if (PI != PE && (PII == PIE || PI->getPointer() < PII->getPointer()))
+        Parser.Note(*PI++, ".personality was specified here");
+      else if (PII != PIE && (PI == PE || PII->getPointer() < PI->getPointer()))
+        Parser.Note(*PII++, ".personalityindex was specified here");
+      else
+        llvm_unreachable(".personality and .personalityindex cannot be "
+                         "at the same location");
+    }
   }
 
   void reset() {
@@ -166,6 +181,7 @@ public:
     CantUnwindLocs = Locs();
     PersonalityLocs = Locs();
     HandlerDataLocs = Locs();
+    PersonalityIndexLocs = Locs();
     FPReg = -1;
   }
 };
@@ -278,6 +294,7 @@ class ARMAsmParser : public MCTargetAsmParser {
   bool parseDirectiveInst(SMLoc L, char Suffix = '\0');
   bool parseDirectiveLtorg(SMLoc L);
   bool parseDirectiveEven(SMLoc L);
+  bool parseDirectivePersonalityIndex(SMLoc L);
 
   StringRef splitMnemonic(StringRef Mnemonic, unsigned &PredicationCode,
                           bool &CarrySetting, unsigned &ProcessorIMod,
@@ -8062,6 +8079,8 @@ bool ARMAsmParser::ParseDirective(AsmToken DirectiveID) {
     return parseDirectiveLtorg(DirectiveID.getLoc());
   else if (IDVal == ".even")
     return parseDirectiveEven(DirectiveID.getLoc());
+  else if (IDVal == ".personalityindex")
+    return parseDirectivePersonalityIndex(DirectiveID.getLoc());
   return true;
 }
 
@@ -8454,6 +8473,9 @@ bool ARMAsmParser::parseDirectiveFnStart(SMLoc L) {
     return false;
   }
 
+  // Reset the unwind directives parser state
+  UC.reset();
+
   getTargetStreamer().emitFnStart();
 
   UC.recordFnStart(L);
@@ -8504,6 +8526,8 @@ bool ARMAsmParser::parseDirectiveCantUnwind(SMLoc L) {
 /// parseDirectivePersonality
 ///  ::= .personality name
 bool ARMAsmParser::parseDirectivePersonality(SMLoc L) {
+  bool HasExistingPersonality = UC.hasPersonality();
+
   UC.recordPersonality(L);
 
   // Check the ordering of unwind directives
@@ -8521,6 +8545,12 @@ bool ARMAsmParser::parseDirectivePersonality(SMLoc L) {
     UC.emitHandlerDataLocNotes();
     return false;
   }
+  if (HasExistingPersonality) {
+    Parser.eatToEndOfStatement();
+    Error(L, "multiple personality directives");
+    UC.emitPersonalityLocNotes();
+    return false;
+  }
 
   // Parse the name of the personality routine
   if (Parser.getTok().isNot(AsmToken::Identifier)) {
@@ -8830,6 +8860,61 @@ bool ARMAsmParser::parseDirectiveEven(SMLoc L) {
   return false;
 }
 
+/// parseDirectivePersonalityIndex
+///   ::= .personalityindex index
+bool ARMAsmParser::parseDirectivePersonalityIndex(SMLoc L) {
+  bool HasExistingPersonality = UC.hasPersonality();
+
+  UC.recordPersonalityIndex(L);
+
+  if (!UC.hasFnStart()) {
+    Parser.eatToEndOfStatement();
+    Error(L, ".fnstart must precede .personalityindex directive");
+    return false;
+  }
+  if (UC.cantUnwind()) {
+    Parser.eatToEndOfStatement();
+    Error(L, ".personalityindex cannot be used with .cantunwind");
+    UC.emitCantUnwindLocNotes();
+    return false;
+  }
+  if (UC.hasHandlerData()) {
+    Parser.eatToEndOfStatement();
+    Error(L, ".personalityindex must precede .handlerdata directive");
+    UC.emitHandlerDataLocNotes();
+    return false;
+  }
+  if (HasExistingPersonality) {
+    Parser.eatToEndOfStatement();
+    Error(L, "multiple personality directives");
+    UC.emitPersonalityLocNotes();
+    return false;
+  }
+
+  const MCExpr *IndexExpression;
+  SMLoc IndexLoc = Parser.getTok().getLoc();
+  if (Parser.parseExpression(IndexExpression)) {
+    Parser.eatToEndOfStatement();
+    return false;
+  }
+
+  const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(IndexExpression);
+  if (!CE) {
+    Parser.eatToEndOfStatement();
+    Error(IndexLoc, "index must be a constant number");
+    return false;
+  }
+  if (CE->getValue() < 0 ||
+      CE->getValue() >= ARM::EHABI::NUM_PERSONALITY_INDEX) {
+    Parser.eatToEndOfStatement();
+    Error(IndexLoc, "personality routine index should be in range [0-3]");
+    return false;
+  }
+
+  getTargetStreamer().emitPersonalityIndex(CE->getValue());
+  return false;
+}
+
 /// Force static initialization.
 extern "C" void LLVMInitializeARMAsmParser() {
   RegisterMCAsmParser<ARMAsmParser> X(TheARMTarget);
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
index 4c079262943..82543a45f24 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -117,6 +117,7 @@ class ARMTargetAsmStreamer : public ARMTargetStreamer {
   virtual void emitFnEnd();
   virtual void emitCantUnwind();
   virtual void emitPersonality(const MCSymbol *Personality);
+  virtual void emitPersonalityIndex(unsigned Index);
   virtual void emitHandlerData();
   virtual void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0);
   virtual void emitPad(int64_t Offset);
@@ -148,6 +149,9 @@ void ARMTargetAsmStreamer::emitCantUnwind() { OS << "\t.cantunwind\n"; }
 void ARMTargetAsmStreamer::emitPersonality(const MCSymbol *Personality) {
   OS << "\t.personality " << Personality->getName() << '\n';
 }
+void ARMTargetAsmStreamer::emitPersonalityIndex(unsigned Index) {
+  OS << "\t.personalityindex " << Index << '\n';
+}
 void ARMTargetAsmStreamer::emitHandlerData() { OS << "\t.handlerdata\n"; }
 void ARMTargetAsmStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
                                      int64_t Offset) {
@@ -357,6 +361,7 @@ private:
   virtual void emitFnEnd();
   virtual void emitCantUnwind();
   virtual void emitPersonality(const MCSymbol *Personality);
+  virtual void emitPersonalityIndex(unsigned Index);
   virtual void emitHandlerData();
   virtual void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0);
   virtual void emitPad(int64_t Offset);
@@ -415,6 +420,7 @@ public:
   void emitFnEnd();
   void emitCantUnwind();
   void emitPersonality(const MCSymbol *Per);
+  void emitPersonalityIndex(unsigned index);
   void emitHandlerData();
   void emitSetFP(unsigned NewFpReg, unsigned NewSpReg, int64_t Offset = 0);
   void emitPad(int64_t Offset);
@@ -614,6 +620,9 @@ void ARMTargetELFStreamer::emitCantUnwind() { getStreamer().emitCantUnwind(); }
 void ARMTargetELFStreamer::emitPersonality(const MCSymbol *Personality) {
   getStreamer().emitPersonality(Personality);
 }
+void ARMTargetELFStreamer::emitPersonalityIndex(unsigned Index) {
+  getStreamer().emitPersonalityIndex(Index);
+}
 void ARMTargetELFStreamer::emitHandlerData() {
   getStreamer().emitHandlerData();
 }
@@ -1135,6 +1144,11 @@ void ARMELFStreamer::emitPersonality(const MCSymbol *Per) {
   UnwindOpAsm.setPersonality(Per);
 }
 
+void ARMELFStreamer::emitPersonalityIndex(unsigned Index) {
+  assert(Index < ARM::EHABI::NUM_PERSONALITY_INDEX && "invalid index");
+  PersonalityIndex = Index;
+}
+
 void ARMELFStreamer::emitSetFP(unsigned NewFPReg, unsigned NewSPReg,
                                int64_t Offset) {
   assert((NewSPReg == ARM::SP || NewSPReg == FPReg) &&
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMUnwindOpAsm.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMUnwindOpAsm.cpp
index 8cba45acf30..593fe349b1d 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMUnwindOpAsm.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMUnwindOpAsm.cpp
@@ -194,14 +194,17 @@ void UnwindOpcodeAssembler::Finalize(unsigned &PersonalityIndex,
     Result.resize(RoundUpSize);
     OpStreamer.EmitSize(RoundUpSize);
   } else {
-    if (Ops.size() <= 3) {
+    // If no personalityindex is specified, select ane
+    if (PersonalityIndex == ARM::EHABI::NUM_PERSONALITY_INDEX)
+      PersonalityIndex = (Ops.size() <= 3) ? ARM::EHABI::AEABI_UNWIND_CPP_PR0
+                                           : ARM::EHABI::AEABI_UNWIND_CPP_PR1;
+    if (PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0) {
       // __aeabi_unwind_cpp_pr0: [ 0x80 , OP1 , OP2 , OP3 ]
-      PersonalityIndex = ARM::EHABI::AEABI_UNWIND_CPP_PR0;
+      assert(Ops.size() <= 3 && "too many opcodes for __aeabi_unwind_cpp_pr0");
       Result.resize(4);
       OpStreamer.EmitPersonalityIndex(PersonalityIndex);
     } else {
-      // __aeabi_unwind_cpp_pr1: [ 0x81 , SIZE , OP1 , OP2 , ... ]
-      PersonalityIndex = ARM::EHABI::AEABI_UNWIND_CPP_PR1;
+      // __aeabi_unwind_cpp_pr{1,2}: [ {0x81,0x82} , SIZE , OP1 , OP2 , ... ]
       size_t TotalSize = Ops.size() + 2;
       size_t RoundUpSize = (TotalSize + 3) / 4 * 4;
       Result.resize(RoundUpSize);