[AsmParser] Support %ty* in force-opaque-pointers mode

[nikic]

Summary

Only enforce that ptr* is illegal if the base type is a simple type, not when it is something like %ty, where %ty may resolve to an opaque pointer in force-opaque-pointers mode.

[aeubanks]

lgtm

llvm/lib/AsmParser/LLParser.cpp

bool LLParser::parseType(Type *&Result, const Twine &Msg, bool AllowVoid) {
   SMLoc TypeLoc = Lex.getLoc();
   switch (Lex.getKind()) {
   default:
     return tokError(Msg);
   case lltok::Type:
     // Type ::= 'float' | 'void' (etc)
     Result = Lex.getTyVal();
     Lex.Lex();
+
+    // Handle (explicit) opaque pointer types (not --force-opaque-pointers).
+    //
+    // Type ::= ptr ('addrspace' '(' uint32 ')')?
+    if (Result->isOpaquePointerTy()) {
+      unsigned AddrSpace;
+      if (parseOptionalAddrSpace(AddrSpace))
+        return true;
+      Result = PointerType::get(getContext(), AddrSpace);
+
+      // Give a nice error for 'ptr*'.
+      if (Lex.getKind() == lltok::star)
+        return tokError("ptr* is invalid - use ptr instead");
+
+      // Fall through to parsing the type suffixes only if this 'ptr' is a
+      // function return. Otherwise, return success, implicitly rejecting other
+      // suffixes.
+      if (Lex.getKind() != lltok::lparen)
+        return false;
+    }
     break;
   case lltok::lbrace:
     // Type ::= StructType
     if (parseAnonStructType(Result, false))
       return true;
     break;
   case lltok::lsquare:
     // Type ::= '[' ... ']'
if (!Entry.first) {
       Entry.second = Lex.getLoc();
     }
     Result = Entry.first;
     Lex.Lex();
     break;
   }
   }
 
-  // Handle (explicit) opaque pointer types (not --force-opaque-pointers).
-  //
-  // Type ::= ptr ('addrspace' '(' uint32 ')')?
-  if (Result->isOpaquePointerTy()) {
-    unsigned AddrSpace;
-    if (parseOptionalAddrSpace(AddrSpace))
-      return true;
-    Result = PointerType::get(getContext(), AddrSpace);
-
-    // Give a nice error for 'ptr*'.
-    if (Lex.getKind() == lltok::star)
-      return tokError("ptr* is invalid - use ptr instead");
-
-    // Fall through to parsing the type suffixes only if this 'ptr' is a
-    // function return. Otherwise, return success, implicitly rejecting other
-    // suffixes.
-    if (Lex.getKind() != lltok::lparen)
-      return false;
-  }
-
   // parse the type suffixes.
   while (true) {
     switch (Lex.getKind()) {
     // End of type.
     default:
       if (!AllowVoid && Result->isVoidTy())
         return error(TypeLoc, "void type only allowed for function results");
       return false;

llvm/test/Other/force-opaque-ptrs.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function-signature
 ; RUN: llvm-as --force-opaque-pointers < %s | llvm-dis --force-opaque-pointers | FileCheck %s
 ; RUN: llvm-as < %s | llvm-dis --force-opaque-pointers | FileCheck %s
 ; RUN: opt --force-opaque-pointers < %s -S | FileCheck %s
 
+%ty = type i32*
+
 ; CHECK: @g = external global i16
 @g = external global i16
 
 ; CHECK: @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 1, ptr null, ptr null }]
 @llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 1, void ()* null, i8* null }]
 
 ; CHECK: @ga = alias i18, ptr @g2
 @g2 = global i18 0

 define void @f3(i32 addrspace(1)* addrspace(2)* %p) {
 ; CHECK-LABEL: define {{[^@]+}}@f3
 ; CHECK-SAME: (ptr addrspace(2) [[P:%.*]]) {
 ; CHECK-NEXT:    unreachable
 ;
   unreachable
 }
 
+define void @f4(%ty* %p) {
+; CHECK-LABEL: define {{[^@]+}}@f4
+; CHECK-SAME: (ptr [[P:%.*]]) {
+; CHECK-NEXT:    unreachable
+;
+  unreachable
+}
+
 define void @remangle_intrinsic() {
 ; CHECK-LABEL: define {{[^@]+}}@remangle_intrinsic() {
 ; CHECK-NEXT:    [[A:%.*]] = alloca ptr, align 8
 ; CHECK-NEXT:    [[TMP1:%.*]] = call ptr @llvm.stacksave()
 ; CHECK-NEXT:    call void @llvm.stackprotector(ptr null, ptr [[A]])
 ; CHECK-NEXT:    [[TMP2:%.*]] = call <2 x i64> @llvm.masked.expandload.v2i64(ptr null, <2 x i1> zeroinitializer, <2 x i64> zeroinitializer)
 ; CHECK-NEXT:    ret void
 ;