4 files changed, 53 insertions, 0 deletions

diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 1e5bcdd930c..962298fcd54 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -612,6 +612,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   KEYWORD(byval);
   KEYWORD(inalloca);
   KEYWORD(cold);
+  KEYWORD(dereferenceable);
   KEYWORD(inlinehint);
   KEYWORD(inreg);
   KEYWORD(jumptable);
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index be55ac6481f..ac6e0e512fe 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -1052,6 +1052,7 @@ bool LLParser::ParseFnAttributeValuePairs(AttrBuilder &B,
               "invalid use of attribute on a function");
       break;
     case lltok::kw_byval:
+    case lltok::kw_dereferenceable:
     case lltok::kw_inalloca:
     case lltok::kw_nest:
     case lltok::kw_noalias:
@@ -1212,6 +1213,16 @@ bool LLParser::ParseUInt32(unsigned &Val) {
   return false;
 }
 
+/// ParseUInt64
+///   ::= uint64
+bool LLParser::ParseUInt64(uint64_t &Val) {
+  if (Lex.getKind() != lltok::APSInt || Lex.getAPSIntVal().isSigned())
+    return TokError("expected integer");
+  Val = Lex.getAPSIntVal().getLimitedValue();
+  Lex.Lex();
+  return false;
+}
+
 /// ParseTLSModel
 ///   := 'localdynamic'
 ///   := 'initialexec'
@@ -1284,6 +1295,13 @@ bool LLParser::ParseOptionalParamAttrs(AttrBuilder &B) {
       continue;
     }
     case lltok::kw_byval:           B.addAttribute(Attribute::ByVal); break;
+    case lltok::kw_dereferenceable: {
+      uint64_t Bytes;
+      if (ParseOptionalDereferenceableBytes(Bytes))
+        return true;
+      B.addDereferenceableAttr(Bytes);
+      continue;
+    }
     case lltok::kw_inalloca:        B.addAttribute(Attribute::InAlloca); break;
     case lltok::kw_inreg:           B.addAttribute(Attribute::InReg); break;
     case lltok::kw_nest:            B.addAttribute(Attribute::Nest); break;
@@ -1341,6 +1359,13 @@ bool LLParser::ParseOptionalReturnAttrs(AttrBuilder &B) {
     switch (Token) {
     default:  // End of attributes.
       return HaveError;
+    case lltok::kw_dereferenceable: {
+      uint64_t Bytes;
+      if (ParseOptionalDereferenceableBytes(Bytes))
+        return true;
+      B.addDereferenceableAttr(Bytes);
+      continue;
+    }
     case lltok::kw_inreg:           B.addAttribute(Attribute::InReg); break;
     case lltok::kw_noalias:         B.addAttribute(Attribute::NoAlias); break;
     case lltok::kw_nonnull:         B.addAttribute(Attribute::NonNull); break;
@@ -1606,6 +1631,26 @@ bool LLParser::ParseOptionalAlignment(unsigned &Alignment) {
   return false;
 }
 
+/// ParseOptionalDereferenceableBytes
+///   ::= /* empty */
+///   ::= 'dereferenceable' '(' 4 ')'
+bool LLParser::ParseOptionalDereferenceableBytes(uint64_t &Bytes) {
+  Bytes = 0;
+  if (!EatIfPresent(lltok::kw_dereferenceable))
+    return false;
+  LocTy ParenLoc = Lex.getLoc();
+  if (!EatIfPresent(lltok::lparen))
+    return Error(ParenLoc, "expected '('");
+  LocTy DerefLoc = Lex.getLoc();
+  if (ParseUInt64(Bytes)) return true;
+  ParenLoc = Lex.getLoc();
+  if (!EatIfPresent(lltok::rparen))
+    return Error(ParenLoc, "expected ')'");
+  if (!Bytes)
+    return Error(DerefLoc, "dereferenceable bytes must be non-zero");
+  return false;
+}
+
 /// ParseOptionalCommaAlign
 ///   ::=
 ///   ::= ',' align 4
diff --git a/llvm/lib/AsmParser/LLParser.h b/llvm/lib/AsmParser/LLParser.h
index 2efb260d66b..7203bb245d0 100644
--- a/llvm/lib/AsmParser/LLParser.h
+++ b/llvm/lib/AsmParser/LLParser.h
@@ -202,6 +202,11 @@ namespace llvm {
       Loc = Lex.getLoc();
       return ParseUInt32(Val);
     }
+    bool ParseUInt64(uint64_t &Val);
+    bool ParseUInt64(uint64_t &Val, LocTy &Loc) {
+      Loc = Lex.getLoc();
+      return ParseUInt64(Val);
+    }
 
     bool ParseTLSModel(GlobalVariable::ThreadLocalMode &TLM);
     bool ParseOptionalThreadLocal(GlobalVariable::ThreadLocalMode &TLM);
@@ -219,6 +224,7 @@ namespace llvm {
     bool ParseOptionalDLLStorageClass(unsigned &DLLStorageClass);
     bool ParseOptionalCallingConv(CallingConv::ID &CC);
     bool ParseOptionalAlignment(unsigned &Alignment);
+    bool ParseOptionalDereferenceableBytes(uint64_t &Bytes);
     bool ParseScopeAndOrdering(bool isAtomic, SynchronizationScope &Scope,
                                AtomicOrdering &Ordering);
     bool ParseOrdering(AtomicOrdering &Ordering);
diff --git a/llvm/lib/AsmParser/LLToken.h b/llvm/lib/AsmParser/LLToken.h
index 534d82415fd..2f02606f93e 100644
--- a/llvm/lib/AsmParser/LLToken.h
+++ b/llvm/lib/AsmParser/LLToken.h
@@ -106,6 +106,7 @@ namespace lltok {
     kw_byval,
     kw_inalloca,
     kw_cold,
+    kw_dereferenceable,
     kw_inlinehint,
     kw_inreg,
     kw_jumptable,