Make CallingConv::ID an alias of "unsigned".

Summary:
Make CallingConv::ID a plain unsigned instead of enum with a
fixed set of valus. LLVM IR allows arbitraty calling conventions (you are
free to write cc12345), and loading them as enum is an undefined
behavior. This was reported by UBSan.

Test Plan: llvm regression test suite

Reviewers: nicholas

Reviewed By: nicholas

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5248

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217529 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/IR/CallingConv.h b/include/llvm/IR/CallingConv.h
index 1eaf4f7f469fe8b252940e816655d971706ccdac..702c35f58fa310ea2ad56cabe13d52167872af4a 100644 (file)
--- a/include/llvm/IR/CallingConv.h
+++ b/include/llvm/IR/CallingConv.h
@@ -20,10 +20,13 @@ namespace llvm {
 /// the well-known calling conventions.
 ///
 namespace CallingConv {
+  /// LLVM IR allows to use arbitrary numbers as calling convention identifiers.
+  typedef unsigned ID;
+
   /// A set of enums which specify the assigned numeric values for known llvm
   /// calling conventions.
   /// @brief LLVM Calling Convention Representation
-  enum ID {
+  enum {
     /// C - The default llvm calling convention, compatible with C.  This
     /// convention is the only calling convention that supports varargs calls.
     /// As with typical C calling conventions, the callee/caller have to

diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index f363b550647a8c78c7e026b3ecc88d965e5227f0..cfdb1d4742faa292703552997fd3765326936906 100644 (file)
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -1464,7 +1464,7 @@ bool LLParser::ParseOptionalDLLStorageClass(unsigned &Res) {
 ///   ::= 'preserve_allcc'
 ///   ::= 'cc' UINT
 ///
-bool LLParser::ParseOptionalCallingConv(CallingConv::ID &CC) {
+bool LLParser::ParseOptionalCallingConv(unsigned &CC) {
   switch (Lex.getKind()) {
   default:                       CC = CallingConv::C; return false;
   case lltok::kw_ccc:            CC = CallingConv::C; break;
@@ -1489,12 +1489,8 @@ bool LLParser::ParseOptionalCallingConv(CallingConv::ID &CC) {
   case lltok::kw_preserve_mostcc:CC = CallingConv::PreserveMost; break;
   case lltok::kw_preserve_allcc: CC = CallingConv::PreserveAll; break;
   case lltok::kw_cc: {
-      unsigned ArbitraryCC;
       Lex.Lex();
-      if (ParseUInt32(ArbitraryCC))
-        return true;
-      CC = static_cast<CallingConv::ID>(ArbitraryCC);
-      return false;
+      return ParseUInt32(CC);
     }
   }
 
@@ -3131,7 +3127,7 @@ bool LLParser::ParseFunctionHeader(Function *&Fn, bool isDefine) {
   unsigned Visibility;
   unsigned DLLStorageClass;
   AttrBuilder RetAttrs;
-  CallingConv::ID CC;
+  unsigned CC;
   Type *RetType = nullptr;
   LocTy RetTypeLoc = Lex.getLoc();
   if (ParseOptionalLinkage(Linkage) ||
@@ -3803,7 +3799,7 @@ bool LLParser::ParseInvoke(Instruction *&Inst, PerFunctionState &PFS) {
   AttrBuilder RetAttrs, FnAttrs;
   std::vector<unsigned> FwdRefAttrGrps;
   LocTy NoBuiltinLoc;
-  CallingConv::ID CC;
+  unsigned CC;
   Type *RetType = nullptr;
   LocTy RetTypeLoc;
   ValID CalleeID;
@@ -4217,7 +4213,7 @@ bool LLParser::ParseCall(Instruction *&Inst, PerFunctionState &PFS,
   AttrBuilder RetAttrs, FnAttrs;
   std::vector<unsigned> FwdRefAttrGrps;
   LocTy BuiltinLoc;
-  CallingConv::ID CC;
+  unsigned CC;
   Type *RetType = nullptr;
   LocTy RetTypeLoc;
   ValID CalleeID;

diff --git a/lib/AsmParser/LLParser.h b/lib/AsmParser/LLParser.h
index b7d8f21442b044f13b3aadc7dc2337849f2f4ab4..aa62bcc8daf02d40657a80d2c1b198da9ac6c6ea 100644 (file)
--- a/lib/AsmParser/LLParser.h
+++ b/lib/AsmParser/LLParser.h
@@ -226,7 +226,7 @@ namespace llvm {
     }
     bool ParseOptionalVisibility(unsigned &Visibility);
     bool ParseOptionalDLLStorageClass(unsigned &DLLStorageClass);
-    bool ParseOptionalCallingConv(CallingConv::ID &CC);
+    bool ParseOptionalCallingConv(unsigned &CC);
     bool ParseOptionalAlignment(unsigned &Alignment);
     bool ParseOptionalDereferenceableBytes(uint64_t &Bytes);
     bool ParseScopeAndOrdering(bool isAtomic, SynchronizationScope &Scope,