[OpenCL] Fix bug in mergeTypes which causes equivalent types treated as different.

[yaxunl]

Summary

When comparing unqualified types, canonical types should be used, otherwise equivalent types may be treated as different type.

For example,

typedef int int_t;
generic int* a;
global int_t* b;

0 ? a : b should have type generic int*. However due to this bug, int_t and int are treated as different types, which causes the type of 0 ? a : b to have type generic void*.

This patch fixes it.

[Anastasia]

test/CodeGenOpenCL/address-spaces-conversions.cl

52 ↗

(On Diff #55417)

Inserting a whitespace here?

[yaxunl]

Removed accidentally inserted blanks.

[Anastasia]

LGTM!

cfe/trunk/lib/AST/ASTContext.cpp

QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
   if (LHSCan == RHSCan)
     return LHS;
 
   // If the qualifiers are different, the types aren't compatible... mostly.
   Qualifiers LQuals = LHSCan.getLocalQualifiers();
   Qualifiers RQuals = RHSCan.getLocalQualifiers();
   if (LQuals != RQuals) {
     if (getLangOpts().OpenCL) {
-      if (LHS.getUnqualifiedType() != RHS.getUnqualifiedType() ||
+      if (LHSCan.getUnqualifiedType() != RHSCan.getUnqualifiedType() ||
           LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers())
         return QualType();
       if (LQuals.isAddressSpaceSupersetOf(RQuals))
         return LHS;
       if (RQuals.isAddressSpaceSupersetOf(LQuals))
         return RHS;
     }
     // If any of these qualifiers are different, we have a type

cfe/trunk/test/CodeGenOpenCL/address-spaces-conversions.cl

void test_ternary(void) {
   // CHECK: store i32 addrspace(4)* %{{.+}}, i32 addrspace(4)** %{{.+}}
 
   var_gen = var_gen ? var_gen : var_glob; // operands of overlapping addr spaces and the same type
   // CHECK: icmp
   // CHECK-NOT: bitcast
   // CHECK: %{{.+}} = addrspacecast i32 addrspace(1)* %{{.+}} to i32 addrspace(4)*
   // CHECK: phi
   // CHECK: store
-  
+  typedef int int_t;
+  global int_t *var_glob_typedef;
+  var_gen = var_gen ? var_gen : var_glob_typedef; // operands of overlapping addr spaces and equivalent types
+  // CHECK: icmp
+  // CHECK-NOT: bitcast
+  // CHECK: %{{.+}} = addrspacecast i32 addrspace(1)* %{{.+}} to i32 addrspace(4)*
+  // CHECK: phi
+  // CHECK: store
+ 
   var_gen_v = var_gen ? var_gen : var_gen_f; // operands of the same addr space and different types
   // CHECK: icmp
   // CHECK: %{{.+}} = bitcast i32 addrspace(4)* %{{.+}} to i8 addrspace(4)*
   // CHECK: %{{.+}} = bitcast float addrspace(4)* %{{.+}} to i8 addrspace(4)*
   // CHECK: phi
   // CHECK: store
 
   var_gen_v = var_gen ? var_glob : var_gen_f; // operands of overlapping addr spaces and different types
   // CHECK: icmp
   // CHECK: %{{.+}} = addrspacecast i32 addrspace(1)* %{{.+}} to i8 addrspace(4)*
   // CHECK: %{{.+}} = bitcast float addrspace(4)* %{{.+}} to i8 addrspace(4)*
   // CHECK: phi
   // CHECK: store
 }