[Go] Subtypes function

[TyanNN]

Summary

This patch adds LLVMGetSubtypes to Go API (as Type.Subtypes), tests included. Please commit this patch if/when everything's OK, as I do not have commit access

[deadalnix]

I don't know go that much so I'll give the opportunity to someone that knows better checks this out.

[TyanNN]

In D33901#773771, @deadalnix wrote:

I don't know go that much so I'll give the opportunity to someone that knows better checks this out.

Well, svn blame said you did some things in go API, so i thought i might as well assign you too

[TyanNN]

ping @pcc

[axw]

Code looks fine, and thanks for adding a test. I just think this one should be a method rather than a free function.

bindings/go/llvm/ir.go

614

I think this should be a method, similar to Type.ParamTypes. I suggest func (t Type) Subtypes() []Type.

bindings/go/llvm/ir_test.go

143

Drop the semicolon, they're unnecessary in Go.

[TyanNN]

Make GetSubtypes a member function of Type. Remove semicolon

[axw]

Sorry, I shouldn't really have said *suggest*. Can you please rename GetSubtypes to Subtypes? GetFoo is not idiomatic in Go (there are some instances of GetFoo in the existing code, but they're stuck like that until someone decides to break compatibility).

[TyanNN]

Rename GetSubtypes to Subtypes

[axw]

Thank you, I'll submit this shortly.

bindings/go/llvm/ir.go

func (t Type) StructElementTypes() []Type {
   out := make([]Type, t.StructElementTypesCount())
   if len(out) > 0 {
     C.LLVMGetStructElementTypes(t.C, llvmTypeRefPtr(&out[0]))
   }
   return out
 }
 
 // Operations on array, pointer, and vector types (sequence types)
+func (t Type) Subtypes() (ret []Type) {
+  ret = make([]Type, C.LLVMGetNumContainedTypes(t.C))
+  C.LLVMGetSubtypes(t.C, llvmTypeRefPtr(&ret[0]))
+  return
+}
+
 func ArrayType(elementType Type, elementCount int) (t Type) {
   t.C = C.LLVMArrayType(elementType.C, C.unsigned(elementCount))
   return
 }
 func PointerType(elementType Type, addressSpace int) (t Type) {
   t.C = C.LLVMPointerType(elementType.C, C.unsigned(addressSpace))
   return
 }

bindings/go/llvm/ir_test.go

func TestDebugLoc(t *testing.T) {
   }
   if loc.Col != 20 {
     t.Errorf("Got column %d, though wanted 20", loc.Col)
   }
   if loc.Scope.C != scope.C {
     t.Errorf("Got metadata %v as scope, though wanted %v", loc.Scope.C, scope.C)
   }
 }
+
+func TestSubtypes(t *testing.T) {
+  cont := NewContext()
+  defer cont.Dispose()
+
+  int_pointer := PointerType(cont.Int32Type(), 0)
+  int_inner := int_pointer.Subtypes()
+  if len(int_inner) != 1 {
+    t.Errorf("Got size %d, though wanted 1")
+  }
+  if int_inner[0] != cont.Int32Type() {
+    t.Errorf("Expected int32 type")
+  }
+
+  st_pointer := cont.StructType([]Type{cont.Int32Type(), cont.Int8Type()}, false)
+  st_inner := st_pointer.Subtypes()
+  if len(st_inner) != 2 {
+    t.Errorf("Got size %d, though wanted 2")
+  }
+  if st_inner[0] != cont.Int32Type() {
+    t.Errorf("Expected first struct field to be int32")
+  }
+  if st_inner[1] != cont.Int8Type() {
+    t.Errorf("Expected second struct field to be int8")
+  }
+}