From 3a86bc9c6d3ca51ce02397f73605a7fbd7f3a899 Mon Sep 17 00:00:00 2001 From: Laytan Laats Date: Fri, 20 Jun 2025 21:56:50 +0200 Subject: [PATCH 1/2] Fix WASM C ABI for raw unions --- src/llvm_abi.cpp | 72 +++++++++++++++++++++++++++------- src/llvm_backend_general.cpp | 2 +- src/types.cpp | 76 ++++++++++++++++++++++++++++++++++++ 3 files changed, 134 insertions(+), 16 deletions(-) diff --git a/src/llvm_abi.cpp b/src/llvm_abi.cpp index af08722c3..e1cbe7558 100644 --- a/src/llvm_abi.cpp +++ b/src/llvm_abi.cpp @@ -1313,7 +1313,7 @@ namespace lbAbiWasm { registers/arguments if possible rather than by pointer. */ gb_internal Array compute_arg_types(LLVMContextRef c, LLVMTypeRef *arg_types, unsigned arg_count, ProcCallingConvention calling_convention, Type *original_type); - gb_internal LB_ABI_COMPUTE_RETURN_TYPE(compute_return_type); + gb_internal lbArgType compute_return_type(lbFunctionType *ft, LLVMContextRef c, LLVMTypeRef return_type, bool return_is_defined, bool return_is_tuple, Type* original_type); enum {MAX_DIRECT_STRUCT_SIZE = 32}; @@ -1323,7 +1323,9 @@ namespace lbAbiWasm { ft->ctx = c; ft->calling_convention = calling_convention; ft->args = compute_arg_types(c, arg_types, arg_count, calling_convention, original_type); - ft->ret = compute_return_type(ft, c, return_type, return_is_defined, return_is_tuple); + + GB_ASSERT(original_type->kind == Type_Proc); + ft->ret = compute_return_type(ft, c, return_type, return_is_defined, return_is_tuple, original_type->Proc.results); return ft; } @@ -1359,7 +1361,7 @@ namespace lbAbiWasm { return false; } - gb_internal bool type_can_be_direct(LLVMTypeRef type, ProcCallingConvention calling_convention) { + gb_internal bool type_can_be_direct(LLVMTypeRef type, Type *original_type, ProcCallingConvention calling_convention) { LLVMTypeKind kind = LLVMGetTypeKind(type); i64 sz = lb_sizeof(type); if (sz == 0) { @@ -1372,9 +1374,21 @@ namespace lbAbiWasm { return false; } else if (kind == LLVMStructTypeKind) { unsigned count = LLVMCountStructElementTypes(type); - if (count == 1) { - return type_can_be_direct(LLVMStructGetTypeAtIndex(type, 0), calling_convention); + + // NOTE(laytan): raw unions are always structs with 1 field in LLVM, need to check our own def. + Type *bt = base_type(original_type); + if (bt->kind == Type_Struct && bt->Struct.is_raw_union) { + count = cast(unsigned)bt->Struct.fields.count; } + + if (count == 1) { + return type_can_be_direct( + LLVMStructGetTypeAtIndex(type, 0), + type_internal_index(original_type, 0), + calling_convention + ); + } + } else if (is_basic_register_type(type)) { return true; } @@ -1398,7 +1412,7 @@ namespace lbAbiWasm { return false; } - gb_internal lbArgType is_struct(LLVMContextRef c, LLVMTypeRef type, ProcCallingConvention calling_convention) { + gb_internal lbArgType is_struct(LLVMContextRef c, LLVMTypeRef type, Type *original_type, ProcCallingConvention calling_convention) { LLVMTypeKind kind = LLVMGetTypeKind(type); GB_ASSERT(kind == LLVMArrayTypeKind || kind == LLVMStructTypeKind); @@ -1406,15 +1420,15 @@ namespace lbAbiWasm { if (sz == 0) { return lb_arg_type_ignore(type); } - if (type_can_be_direct(type, calling_convention)) { + if (type_can_be_direct(type, original_type, calling_convention)) { return lb_arg_type_direct(type); } return lb_arg_type_indirect(type, nullptr); } - gb_internal lbArgType pseudo_slice(LLVMContextRef c, LLVMTypeRef type, ProcCallingConvention calling_convention) { + gb_internal lbArgType pseudo_slice(LLVMContextRef c, LLVMTypeRef type, Type *original_type, ProcCallingConvention calling_convention) { if (build_context.metrics.ptr_size < build_context.metrics.int_size && - type_can_be_direct(type, calling_convention)) { + type_can_be_direct(type, original_type, calling_convention)) { LLVMTypeRef types[2] = { LLVMStructGetTypeAtIndex(type, 0), // ignore padding @@ -1423,7 +1437,7 @@ namespace lbAbiWasm { LLVMTypeRef new_type = LLVMStructTypeInContext(c, types, gb_count_of(types), false); return lb_arg_type_direct(type, new_type, nullptr, nullptr); } else { - return is_struct(c, type, calling_convention); + return is_struct(c, type, original_type, calling_convention); } } @@ -1444,9 +1458,9 @@ namespace lbAbiWasm { LLVMTypeKind kind = LLVMGetTypeKind(t); if (kind == LLVMStructTypeKind || kind == LLVMArrayTypeKind) { if (is_type_slice(ptype) || is_type_string(ptype)) { - args[i] = pseudo_slice(c, t, calling_convention); + args[i] = pseudo_slice(c, t, ptype, calling_convention); } else { - args[i] = is_struct(c, t, calling_convention); + args[i] = is_struct(c, t, ptype, calling_convention); } } else { args[i] = non_struct(c, t, false); @@ -1455,11 +1469,11 @@ namespace lbAbiWasm { return args; } - gb_internal LB_ABI_COMPUTE_RETURN_TYPE(compute_return_type) { + gb_internal lbArgType compute_return_type(lbFunctionType *ft, LLVMContextRef c, LLVMTypeRef return_type, bool return_is_defined, bool return_is_tuple, Type* original_type) { if (!return_is_defined) { return lb_arg_type_direct(LLVMVoidTypeInContext(c)); } else if (lb_is_type_kind(return_type, LLVMStructTypeKind) || lb_is_type_kind(return_type, LLVMArrayTypeKind)) { - if (type_can_be_direct(return_type, ft->calling_convention)) { + if (type_can_be_direct(return_type, original_type, ft->calling_convention)) { return lb_arg_type_direct(return_type); } else if (ft->calling_convention != ProcCC_CDecl) { i64 sz = lb_sizeof(return_type); @@ -1471,7 +1485,35 @@ namespace lbAbiWasm { } } - LB_ABI_MODIFY_RETURN_IF_TUPLE_MACRO(); + // Multiple returns. + if (return_is_tuple) { \ + lbArgType return_arg = {}; + if (lb_is_type_kind(return_type, LLVMStructTypeKind)) { + unsigned field_count = LLVMCountStructElementTypes(return_type); + if (field_count > 1) { + ft->original_arg_count = ft->args.count; + ft->multiple_return_original_type = return_type; + + for (unsigned i = 0; i < field_count-1; i++) { + LLVMTypeRef field_type = LLVMStructGetTypeAtIndex(return_type, i); + LLVMTypeRef field_pointer_type = LLVMPointerType(field_type, 0); + lbArgType ret_partial = lb_arg_type_direct(field_pointer_type); + array_add(&ft->args, ret_partial); + } + + return_arg = compute_return_type( + ft, + c, + LLVMStructGetTypeAtIndex(return_type, field_count-1), + true, false, + type_internal_index(original_type, field_count-1) + ); + } + } + if (return_arg.type != nullptr) { + return return_arg; + } + } LLVMAttributeRef attr = lb_create_enum_attribute_with_type(c, "sret", return_type); return lb_arg_type_indirect(return_type, attr); diff --git a/src/llvm_backend_general.cpp b/src/llvm_backend_general.cpp index 5aaa7f63a..5d6a55973 100644 --- a/src/llvm_backend_general.cpp +++ b/src/llvm_backend_general.cpp @@ -2206,7 +2206,7 @@ gb_internal LLVMTypeRef lb_type_internal(lbModule *m, Type *type) { field_count = 3; } LLVMTypeRef *fields = gb_alloc_array(permanent_allocator(), LLVMTypeRef, field_count); - fields[0] = LLVMPointerType(lb_type(m, type->Pointer.elem), 0); + fields[0] = LLVMPointerType(lb_type(m, type->SoaPointer.elem), 0); if (bigger_int) { fields[1] = lb_type_padding_filler(m, build_context.ptr_size, build_context.ptr_size); fields[2] = LLVMIntTypeInContext(ctx, 8*cast(unsigned)build_context.int_size); diff --git a/src/types.cpp b/src/types.cpp index c7573173c..861aa5bf8 100644 --- a/src/types.cpp +++ b/src/types.cpp @@ -4614,6 +4614,82 @@ gb_internal Type *alloc_type_proc_from_types(Type **param_types, unsigned param_ // return type; // } +// Index a type that is internally a struct or array. +gb_internal Type *type_internal_index(Type *t, isize index) { + Type *bt = base_type(t); + if (bt == nullptr) { + return nullptr; + } + + switch (bt->kind) { + case Type_Basic: + { + switch (bt->Basic.kind) { + case Basic_complex32: return t_f16; + case Basic_complex64: return t_f32; + case Basic_complex128: return t_f64; + case Basic_quaternion64: return t_f16; + case Basic_quaternion128: return t_f32; + case Basic_quaternion256: return t_f64; + case Basic_string: + { + GB_ASSERT(index == 0 || index == 1); + return index == 0 ? t_u8_ptr : t_int; + } + case Basic_any: + { + GB_ASSERT(index == 0 || index == 1); + return index == 0 ? t_rawptr : t_typeid; + } + } + } + break; + + case Type_Array: return bt->Array.elem; + case Type_EnumeratedArray: return bt->EnumeratedArray.elem; + case Type_SimdVector: return bt->SimdVector.elem; + case Type_Slice: + { + GB_ASSERT(index == 0 || index == 1); + return index == 0 ? t_rawptr : t_typeid; + } + case Type_DynamicArray: + { + switch (index) { + case 0: return t_rawptr; + case 1: return t_int; + case 2: return t_int; + case 3: return t_allocator; + default: GB_PANIC("invalid raw dynamic array index"); + }; + } + case Type_Struct: + return get_struct_field_type(bt, index); + case Type_Union: + if (index < bt->Union.variants.count) { + return bt->Union.variants[index]; + } + return union_tag_type(bt); + case Type_Tuple: + return bt->Tuple.variables[index]->type; + case Type_Matrix: + return bt->Matrix.elem; + case Type_SoaPointer: + { + GB_ASSERT(index == 0 || index == 1); + return index == 0 ? t_rawptr : t_int; + } + case Type_Map: + return type_internal_index(bt->Map.debug_metadata_type, index); + case Type_BitField: + return type_internal_index(bt->BitField.backing_type, index); + case Type_Generic: + return type_internal_index(bt->Generic.specialized, index); + }; + + GB_PANIC("Unhandled type %s", type_to_string(bt)); +}; + gb_internal gbString write_type_to_string(gbString str, Type *type, bool shorthand=false, bool allow_polymorphic=false) { if (type == nullptr) { return gb_string_appendc(str, ""); From 3db8972c990746557916aa640842817094f9ecff Mon Sep 17 00:00:00 2001 From: Laytan Laats Date: Fri, 20 Jun 2025 22:07:46 +0200 Subject: [PATCH 2/2] add return --- src/types.cpp | 1 + 1 file changed, 1 insertion(+) diff --git a/src/types.cpp b/src/types.cpp index 861aa5bf8..cb353516d 100644 --- a/src/types.cpp +++ b/src/types.cpp @@ -4688,6 +4688,7 @@ gb_internal Type *type_internal_index(Type *t, isize index) { }; GB_PANIC("Unhandled type %s", type_to_string(bt)); + return nullptr; }; gb_internal gbString write_type_to_string(gbString str, Type *type, bool shorthand=false, bool allow_polymorphic=false) {