LLVMValueRef gendesc_istrait(compile_t* c, LLVMValueRef desc, ast_t* type)
{
// Get the trait identifier.
reach_type_t* t = reach_type(c->reach, type);
assert(t != NULL);
LLVMValueRef trait_id = LLVMConstInt(c->i32, t->type_id, false);
// Read the count and the trait list from the descriptor.
LLVMValueRef count = desc_field(c, desc, DESC_TRAIT_COUNT);
LLVMValueRef list = desc_field(c, desc, DESC_TRAITS);
LLVMBasicBlockRef entry_block = LLVMGetInsertBlock(c->builder);
LLVMBasicBlockRef cond_block = codegen_block(c, "cond");
LLVMBasicBlockRef body_block = codegen_block(c, "body");
LLVMBasicBlockRef post_block = codegen_block(c, "post");
LLVMBuildBr(c->builder, cond_block);
// While the index is less than the count, check an ID.
LLVMPositionBuilderAtEnd(c->builder, cond_block);
LLVMValueRef phi = LLVMBuildPhi(c->builder, c->i32, "");
LLVMValueRef zero = LLVMConstInt(c->i32, 0, false);
LLVMAddIncoming(phi, &zero, &entry_block, 1);
LLVMValueRef test = LLVMBuildICmp(c->builder, LLVMIntULT, phi, count, "");
LLVMBuildCondBr(c->builder, test, body_block, post_block);
// The phi node is the index. Get ID and compare it.
LLVMPositionBuilderAtEnd(c->builder, body_block);
LLVMValueRef gep[2];
gep[0] = LLVMConstInt(c->i32, 0, false);
gep[1] = phi;
LLVMValueRef id_ptr = LLVMBuildInBoundsGEP(c->builder, list, gep, 2, "");
LLVMValueRef id = LLVMBuildLoad(c->builder, id_ptr, "");
LLVMValueRef test_id = LLVMBuildICmp(c->builder, LLVMIntEQ, id, trait_id,
"");
// Add one to the phi node.
LLVMValueRef one = LLVMConstInt(c->i32, 1, false);
LLVMValueRef inc = LLVMBuildAdd(c->builder, phi, one, "");
LLVMAddIncoming(phi, &inc, &body_block, 1);
// Either to the post block or back to the condition.
LLVMBuildCondBr(c->builder, test_id, post_block, cond_block);
LLVMPositionBuilderAtEnd(c->builder, post_block);
LLVMValueRef result = LLVMBuildPhi(c->builder, c->i1, "");
LLVMAddIncoming(result, &test, &cond_block, 1);
LLVMAddIncoming(result, &test_id, &body_block, 1);
return result;
}
LLVMValueRef gendesc_ptr_to_fields(compile_t* c, LLVMValueRef object,
LLVMValueRef desc)
{
// Skip the descriptor.
LLVMValueRef offset = desc_field(c, desc, DESC_FIELD_OFFSET);
offset = LLVMBuildZExt(c->builder, offset, c->intptr, "");
LLVMValueRef base = LLVMBuildBitCast(c->builder, object, c->void_ptr, "");
return LLVMBuildInBoundsGEP(c->builder, base, &offset, 1, "");
}
LLVMValueRef gendesc_fieldinfo(compile_t* c, LLVMValueRef desc, size_t index)
{
LLVMValueRef fields = desc_field(c, desc, DESC_FIELDS);
LLVMValueRef gep[2];
gep[0] = LLVMConstInt(c->i32, 0, false);
gep[1] = LLVMConstInt(c->i32, index, false);
LLVMValueRef field_desc = LLVMBuildGEP(c->builder, fields, gep, 2, "");
return LLVMBuildLoad(c->builder, field_desc, "");
}
LLVMValueRef gendesc_ptr_to_fields(compile_t* c, LLVMValueRef object,
LLVMValueRef desc)
{
// Skip the descriptor.
LLVMValueRef offset = desc_field(c, desc, DESC_FIELD_OFFSET);
offset = LLVMBuildZExt(c->builder, offset, c->intptr, "");
LLVMValueRef base = LLVMBuildPtrToInt(c->builder, object, c->intptr, "");
LLVMValueRef result = LLVMBuildAdd(c->builder, base, offset, "");
// Return as a c->intptr.
return result;
}
LLVMValueRef gendesc_fieldcount(compile_t* c, LLVMValueRef desc)
{
return desc_field(c, desc, DESC_FIELD_COUNT);
}
LLVMValueRef gendesc_dispatch(compile_t* c, LLVMValueRef object)
{
return desc_field(c, gendesc_fetch(c, object), DESC_DISPATCH);
}
LLVMValueRef gendesc_trace(compile_t* c, LLVMValueRef object)
{
return desc_field(c, gendesc_fetch(c, object), DESC_TRACE);
}
