Initial commit of the 'landingpad' instruction.

This implements the 'landingpad' instruction. It's used to indicate that a basic
block is a landing pad. There are several restrictions on its use (see
LangRef.html for more detail). These restrictions allow the exception handling
code to gather the information it needs in a much more sane way.

This patch has the definition, implementation, C interface, parsing, and bitcode
support in it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137501 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 51 insertions, 0 deletions

diff --git a/lib/AsmParser/LLLexer.cpp b/lib/AsmParser/LLLexer.cpp
index c3a5a4d0db..fdadd1ba93 100644
--- a/lib/AsmParser/LLLexer.cpp
+++ b/lib/AsmParser/LLLexer.cpp
@@ -584,6 +584,11 @@ lltok::Kind LLLexer::LexIdentifier() {
 
   KEYWORD(x);
   KEYWORD(blockaddress);
+
+  KEYWORD(personality);
+  KEYWORD(cleanup);
+  KEYWORD(catch);
+  KEYWORD(filter);
 #undef KEYWORD
 
   // Keywords for types.
@@ -653,6 +658,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   INSTKEYWORD(shufflevector,  ShuffleVector);
   INSTKEYWORD(extractvalue,   ExtractValue);
   INSTKEYWORD(insertvalue,    InsertValue);
+  INSTKEYWORD(landingpad,     LandingPad);
 #undef INSTKEYWORD
 
   // Check for [us]0x[0-9A-Fa-f]+ which are Hexadecimal constant generated by
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 8b30eef3d5..6a4c2a8fb9 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -2945,6 +2945,7 @@ int LLParser::ParseInstruction(Instruction *&Inst, BasicBlock *BB,
   case lltok::kw_insertelement:  return ParseInsertElement(Inst, PFS);
   case lltok::kw_shufflevector:  return ParseShuffleVector(Inst, PFS);
   case lltok::kw_phi:            return ParsePHI(Inst, PFS);
+  case lltok::kw_landingpad:     return ParseLandingPad(Inst, PFS);
   case lltok::kw_call:           return ParseCall(Inst, PFS, false);
   case lltok::kw_tail:           return ParseCall(Inst, PFS, true);
   // Memory.
@@ -3519,6 +3520,47 @@ int LLParser::ParsePHI(Instruction *&Inst, PerFunctionState &PFS) {
   return AteExtraComma ? InstExtraComma : InstNormal;
 }
 
+/// ParseLandingPad
+///   ::= 'landingpad' Type 'personality' TypeAndValue 'cleanup'? Clause+
+/// Clause
+///   ::= 'catch' TypeAndValue
+///   ::= 'filter'
+///   ::= 'filter' TypeAndValue ( ',' TypeAndValue )*
+bool LLParser::ParseLandingPad(Instruction *&Inst, PerFunctionState &PFS) {
+  Type *Ty = 0; LocTy TyLoc;
+  Value *PersFn; LocTy PersFnLoc;
+  LocTy LPLoc = Lex.getLoc();
+
+  if (ParseType(Ty, TyLoc) ||
+      ParseToken(lltok::kw_personality, "expected 'personality'") ||
+      ParseTypeAndValue(PersFn, PersFnLoc, PFS))
+    return true;
+
+  LandingPadInst *LP = LandingPadInst::Create(Ty, PersFn, 0);
+  LP->setCleanup(EatIfPresent(lltok::kw_cleanup));
+
+  while (Lex.getKind() == lltok::kw_catch || Lex.getKind() == lltok::kw_filter){
+    LandingPadInst::ClauseType CT;
+    if (EatIfPresent(lltok::kw_catch))
+      CT = LandingPadInst::Catch;
+    else if (EatIfPresent(lltok::kw_filter))
+      CT = LandingPadInst::Filter;
+    else
+      return TokError("expected 'catch' or 'filter' clause type");
+
+    Value *V; LocTy VLoc;
+    if (ParseTypeAndValue(V, VLoc, PFS)) {
+      delete LP;
+      return true;
+    }
+
+    LP->addClause(V);
+  }
+
+  Inst = LP;
+  return false;
+}
+
 /// ParseCall
 ///   ::= 'tail'? 'call' OptionalCallingConv OptionalAttrs Type Value
 ///       ParameterList OptionalAttrs
diff --git a/lib/AsmParser/LLParser.h b/lib/AsmParser/LLParser.h
index 815f062026..ef4d3dba9e 100644
--- a/lib/AsmParser/LLParser.h
+++ b/lib/AsmParser/LLParser.h
@@ -360,6 +360,7 @@ namespace llvm {
     bool ParseInsertElement(Instruction *&I, PerFunctionState &PFS);
     bool ParseShuffleVector(Instruction *&I, PerFunctionState &PFS);
     int ParsePHI(Instruction *&I, PerFunctionState &PFS);
+    bool ParseLandingPad(Instruction *&I, PerFunctionState &PFS);
     bool ParseCall(Instruction *&I, PerFunctionState &PFS, bool isTail);
     int ParseAlloc(Instruction *&I, PerFunctionState &PFS);
     int ParseLoad(Instruction *&I, PerFunctionState &PFS,
diff --git a/lib/AsmParser/LLToken.h b/lib/AsmParser/LLToken.h
index 3da85ad5d7..d22ecf31bd 100644
--- a/lib/AsmParser/LLToken.h
+++ b/lib/AsmParser/LLToken.h
@@ -124,6 +124,8 @@ namespace lltok {
     kw_fptoui, kw_fptosi, kw_inttoptr, kw_ptrtoint, kw_bitcast,
     kw_select, kw_va_arg,
 
+    kw_landingpad, kw_personality, kw_cleanup, kw_catch, kw_filter,
+
     kw_ret, kw_br, kw_switch, kw_indirectbr, kw_invoke, kw_unwind, kw_resume,
     kw_unreachable,