[Phabricator] Fix __ptr32 arguments passed to builtins

[Ariel-Burton]

Summary

Currently when clang deals with a call to a builtin function that
is supplied with an argument that has an explicit address space
it rewrites the signature of the callee to make the types of
the formal parameters match those of the actual arguments.
This functionality was added to support OpenCL, and was
introduced with commit b919c7d.

However, this does not work properly for "size" related address
spaces such as those used for __ptr32. This affects platforms
like Microsoft and z/OS.

This change preserves the OpenCL functionality, but will use
the formal parameter types when an address space is size-related.

[Ariel-Burton]

• Adjust formatting to conform to git-clang-format

[arichardson]

It sounds to me that the logic from b919c7d should have been restricted to actual LLVM intrinsics that are overloaded on the pointer args ( e.g. llvm.memcpy which was the test in that commit). Builtins that are just library calls with known semantics probably need the cast even for opencl?

clang/test/CodeGen/address-space-ptr32.c

54

Maybe use __builtin_strlen here instead to avoid the declaration?

clang/lib/Sema/SemaExpr.cpp

for (QualType ParamType : FT->param_types()) {
 
     // Convert array arguments to pointer to simplify type lookup.
     ExprResult ArgRes =
         Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]);
     if (ArgRes.isInvalid())
       return nullptr;
     Expr *Arg = ArgRes.get();
     QualType ArgType = Arg->getType();
-    if (!ParamType->isPointerType() ||
-        ParamType.hasAddressSpace() ||
+    if (!ParamType->isPointerType() || ParamType.hasAddressSpace() ||
         !ArgType->isPointerType() ||
-        !ArgType->getPointeeType().hasAddressSpace()) {
+        !ArgType->getPointeeType().hasAddressSpace() ||
+        isPtrSizeAddressSpace(ArgType->getPointeeType().getAddressSpace())) {
       OverloadParams.push_back(ParamType);
       continue;
     }
 
     QualType PointeeType = ParamType->getPointeeType();
     if (PointeeType.hasAddressSpace())
       continue;
 

clang/test/CodeGen/address-space-ptr32.c

int fugu(void) {
   // CHECK: define dso_local i32 @fugu
   // CHECK: %p = alloca ptr addrspace(270), align 4
   // CHECK: ret i32 4
   typedef int *int_star;
 
   int_star __ptr32 p;
   return sizeof(p);
 }
+
+typedef __SIZE_TYPE__ size_t;
+size_t strlen(const char *);
+
+size_t test_calling_strlen_with_32_bit_pointer ( char *__ptr32 s ) {
+  // CHECK-LABEL: define dso_local i64 @test_calling_strlen_with_32_bit_pointer(ptr addrspace(270) noundef %s)
+  // CHECK-NEXT: entry:
+  // CHECK-NEXT:   %s.addr = alloca ptr addrspace(270), align 4
+  // CHECK-NEXT:   store ptr addrspace(270) %s, ptr %s.addr, align 4
+  // CHECK-NEXT:   %0 = load ptr addrspace(270), ptr %s.addr, align 4
+  // CHECK-NEXT:   %1 = addrspacecast ptr addrspace(270) %0 to ptr
+  // CHECK-NEXT:   %call = call i64 @strlen(ptr  noundef %1)
+  // CHECK-NEXT:   ret i64 %call
+   return strlen ( s );
+}
+
+// CHECK-LABEL: declare dso_local i64 @strlen(ptr noundef)
+
+size_t test_calling_strlen_with_64_bit_pointer ( char *s ) {
+  // CHECK-LABEL: define dso_local i64 @test_calling_strlen_with_64_bit_pointer(ptr noundef %s)
+  // CHECK-NEXT: entry:
+  // CHECK-NEXT:   %s.addr = alloca ptr, align 8
+  // CHECK-NEXT:   store ptr %s, ptr %s.addr, align 8
+  // CHECK-NEXT:   %0 = load ptr, ptr %s.addr, align 8
+  // CHECK-NEXT:   %call = call i64 @strlen(ptr noundef %0)
+  // CHECK-NEXT:   ret i64 %call
+  return strlen ( s );
+}