From 17b1ac5d03cd32e047d917a88e029c143cb5d119 Mon Sep 17 00:00:00 2001 From: Andrew Kelley Date: Mon, 10 Jun 2019 12:24:19 -0400 Subject: [PATCH] result location semantics for `@bitCast` ```zig export fn entry() void { var x = @bitCast(f32, foo()); } ``` ```llvm define void @entry() #2 !dbg !35 { Entry: %x = alloca float, align 4 %0 = bitcast float* %x to %Foo*, !dbg !42 call fastcc void @foo(%Foo* sret %0), !dbg !42 call void @llvm.dbg.declare(metadata float* %x, metadata !39, metadata !DIExpression()), !dbg !43 ret void, !dbg !44 } ``` --- BRANCH_TODO | 4 +- src/all_types.hpp | 18 +++-- src/codegen.cpp | 14 +--- src/ir.cpp | 178 ++++++++++++++++++++++------------------------ src/ir_print.cpp | 19 +++-- 5 files changed, 103 insertions(+), 130 deletions(-) diff --git a/BRANCH_TODO b/BRANCH_TODO index 2744901bf..296d8a24f 100644 --- a/BRANCH_TODO +++ b/BRANCH_TODO @@ -1,8 +1,6 @@ Scratch pad for stuff to do before merging master ================================================= - * bitCast - look at all the ir_gen_node ir_gen_node_extra calls and make sure result locations are properly propagated return ir_gen_comptime(irb, scope, node, lval); @@ -23,3 +21,5 @@ inferred comptime return ir_build_ref(irb, scope, value->source_node, value, false, false); handle if with no else + + diff --git a/src/all_types.hpp b/src/all_types.hpp index 35e9786ba..ef4d94880 100644 --- a/src/all_types.hpp +++ b/src/all_types.hpp @@ -2267,7 +2267,6 @@ enum IrInstructionId { IrInstructionIdTestComptime, IrInstructionIdPtrCastSrc, IrInstructionIdPtrCastGen, - IrInstructionIdBitCast, IrInstructionIdBitCastGen, IrInstructionIdWidenOrShorten, IrInstructionIdIntToPtr, @@ -2645,7 +2644,6 @@ struct IrInstructionContainerInitList { IrInstruction *elem_type; size_t item_count; IrInstruction **items; - LLVMValueRef tmp_ptr; }; struct IrInstructionContainerInitFieldsField { @@ -3136,18 +3134,10 @@ struct IrInstructionPtrCastGen { bool safety_check_on; }; -struct IrInstructionBitCast { - IrInstruction base; - - IrInstruction *dest_type; - IrInstruction *value; -}; - struct IrInstructionBitCastGen { IrInstruction base; IrInstruction *operand; - LLVMValueRef tmp_ptr; }; struct IrInstructionWidenOrShorten { @@ -3590,6 +3580,7 @@ enum ResultLocId { ResultLocIdPeer, ResultLocIdPeerParent, ResultLocIdInstruction, + ResultLocIdBitCast, }; struct ResultLoc { @@ -3644,6 +3635,13 @@ struct ResultLocInstruction { ResultLoc base; }; +// The source_instruction is the destination type +struct ResultLocBitCast { + ResultLoc base; + + ResultLoc *parent; +}; + static const size_t slice_ptr_index = 0; static const size_t slice_len_index = 1; diff --git a/src/codegen.cpp b/src/codegen.cpp index eb2e92f62..894d22d47 100644 --- a/src/codegen.cpp +++ b/src/codegen.cpp @@ -3145,12 +3145,7 @@ static LLVMValueRef ir_render_bit_cast(CodeGen *g, IrExecutable *executable, uint32_t alignment = get_abi_alignment(g, actual_type); return gen_load_untyped(g, bitcasted_ptr, alignment, false, ""); } else { - assert(instruction->tmp_ptr != nullptr); - LLVMTypeRef wanted_ptr_type_ref = LLVMPointerType(get_llvm_type(g, actual_type), 0); - LLVMValueRef bitcasted_ptr = LLVMBuildBitCast(g->builder, instruction->tmp_ptr, wanted_ptr_type_ref, ""); - uint32_t alignment = get_abi_alignment(g, wanted_type); - gen_store_untyped(g, value, bitcasted_ptr, alignment, false); - return instruction->tmp_ptr; + zig_unreachable(); } } @@ -5520,7 +5515,6 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable, case IrInstructionIdPtrCastSrc: case IrInstructionIdCmpxchgSrc: case IrInstructionIdLoadPtr: - case IrInstructionIdBitCast: case IrInstructionIdGlobalAsm: case IrInstructionIdHasDecl: case IrInstructionIdUndeclaredIdent: @@ -6837,9 +6831,6 @@ static void do_code_gen(CodeGen *g) { slot = &ref_instruction->tmp_ptr; assert(instruction->value.type->id == ZigTypeIdPointer); slot_type = instruction->value.type->data.pointer.child_type; - } else if (instruction->id == IrInstructionIdContainerInitList) { - IrInstructionContainerInitList *container_init_list_instruction = (IrInstructionContainerInitList *)instruction; - slot = &container_init_list_instruction->tmp_ptr; } else if (instruction->id == IrInstructionIdSlice) { IrInstructionSlice *slice_instruction = (IrInstructionSlice *)instruction; slot = &slice_instruction->tmp_ptr; @@ -6861,9 +6852,6 @@ static void do_code_gen(CodeGen *g) { } else if (instruction->id == IrInstructionIdLoadPtrGen) { IrInstructionLoadPtrGen *load_ptr_inst = (IrInstructionLoadPtrGen *)instruction; slot = &load_ptr_inst->tmp_ptr; - } else if (instruction->id == IrInstructionIdBitCastGen) { - IrInstructionBitCastGen *bit_cast_inst = (IrInstructionBitCastGen *)instruction; - slot = &bit_cast_inst->tmp_ptr; } else if (instruction->id == IrInstructionIdVectorToArray) { IrInstructionVectorToArray *vector_to_array_instruction = (IrInstructionVectorToArray *)instruction; alignment_bytes = get_abi_alignment(g, vector_to_array_instruction->vector->value.type); diff --git a/src/ir.cpp b/src/ir.cpp index 05f95a248..26d0d59b2 100644 --- a/src/ir.cpp +++ b/src/ir.cpp @@ -780,10 +780,6 @@ static constexpr IrInstructionId ir_instruction_id(IrInstructionPtrCastGen *) { return IrInstructionIdPtrCastGen; } -static constexpr IrInstructionId ir_instruction_id(IrInstructionBitCast *) { - return IrInstructionIdBitCast; -} - static constexpr IrInstructionId ir_instruction_id(IrInstructionBitCastGen *) { return IrInstructionIdBitCastGen; } @@ -2429,20 +2425,6 @@ static IrInstruction *ir_build_load_ptr_gen(IrAnalyze *ira, IrInstruction *sourc return &instruction->base; } -static IrInstruction *ir_build_bit_cast(IrBuilder *irb, Scope *scope, AstNode *source_node, - IrInstruction *dest_type, IrInstruction *value) -{ - IrInstructionBitCast *instruction = ir_build_instruction( - irb, scope, source_node); - instruction->dest_type = dest_type; - instruction->value = value; - - ir_ref_instruction(dest_type, irb->current_basic_block); - ir_ref_instruction(value, irb->current_basic_block); - - return &instruction->base; -} - static IrInstruction *ir_build_bit_cast_gen(IrAnalyze *ira, IrInstruction *source_instruction, IrInstruction *operand, ZigType *ty) { @@ -4836,18 +4818,23 @@ static IrInstruction *ir_gen_builtin_fn_call(IrBuilder *irb, Scope *scope, AstNo } case BuiltinFnIdBitCast: { - AstNode *arg0_node = node->data.fn_call_expr.params.at(0); - IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope); - if (arg0_value == irb->codegen->invalid_instruction) - return arg0_value; + AstNode *dest_type_node = node->data.fn_call_expr.params.at(0); + IrInstruction *dest_type = ir_gen_node(irb, dest_type_node, scope); + if (dest_type == irb->codegen->invalid_instruction) + return dest_type; + + ResultLocBitCast *result_loc_bit_cast = allocate(1); + result_loc_bit_cast->base.id = ResultLocIdBitCast; + result_loc_bit_cast->base.source_instruction = dest_type; + result_loc_bit_cast->parent = result_loc; AstNode *arg1_node = node->data.fn_call_expr.params.at(1); - IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope); + IrInstruction *arg1_value = ir_gen_node_extra(irb, arg1_node, scope, LValNone, + &result_loc_bit_cast->base); if (arg1_value == irb->codegen->invalid_instruction) return arg1_value; - IrInstruction *bit_cast = ir_build_bit_cast(irb, scope, node, arg0_value, arg1_value); - return ir_lval_wrap(irb, scope, bit_cast, lval, result_loc); + return ir_lval_wrap(irb, scope, arg1_value, lval, result_loc); } case BuiltinFnIdIntToPtr: { @@ -14059,9 +14046,10 @@ static IrInstruction *ir_analyze_instruction_decl_var(IrAnalyze *ira, bool var_class_requires_const = false; IrInstruction *var_ptr = decl_var_instruction->ptr->child; - // if this assertion trips there may be a missing ir_expr_wrap in pass1 IR generation. - ir_assert(var_ptr != nullptr, &decl_var_instruction->base); - if (type_is_invalid(var_ptr->value.type)) { + // if this is null, a compiler error happened and did not initialize the variable. + // if there are no compile errors there may be a missing ir_expr_wrap in pass1 IR generation. + if (var_ptr == nullptr || type_is_invalid(var_ptr->value.type)) { + ir_assert(var_ptr != nullptr || ira->codegen->errors.length != 0, &decl_var_instruction->base); var->var_type = ira->codegen->builtin_types.entry_invalid; return ira->codegen->invalid_instruction; } @@ -14528,6 +14516,7 @@ static ZigType *ir_result_loc_expected_type(IrAnalyze *ira, IrInstruction *suspe zig_unreachable(); case ResultLocIdNone: case ResultLocIdVar: + case ResultLocIdBitCast: return nullptr; case ResultLocIdInstruction: return result_loc->source_instruction->child->value.type; @@ -14539,6 +14528,28 @@ static ZigType *ir_result_loc_expected_type(IrAnalyze *ira, IrInstruction *suspe zig_unreachable(); } +static bool type_can_bit_cast(ZigType *t) { + switch (t->id) { + case ZigTypeIdInvalid: + zig_unreachable(); + case ZigTypeIdMetaType: + case ZigTypeIdOpaque: + case ZigTypeIdBoundFn: + case ZigTypeIdArgTuple: + case ZigTypeIdUnreachable: + case ZigTypeIdComptimeFloat: + case ZigTypeIdComptimeInt: + case ZigTypeIdEnumLiteral: + case ZigTypeIdUndefined: + case ZigTypeIdNull: + case ZigTypeIdPointer: + return false; + default: + // TODO list these types out explicitly, there are probably some other invalid ones here + return true; + } +} + // give nullptr for value to resolve it at runtime // returns a result location, or nullptr if the result location was already taken care of // when calling this function, at the callsite must check for result type noreturn and propagate it up @@ -14676,6 +14687,50 @@ static IrInstruction *ir_resolve_result(IrAnalyze *ira, IrInstruction *suspend_s result_loc->resolved_loc = parent_result_loc; return result_loc->resolved_loc; } + case ResultLocIdBitCast: { + ResultLocBitCast *result_bit_cast = reinterpret_cast(result_loc); + ZigType *dest_type = ir_resolve_type(ira, result_bit_cast->base.source_instruction->child); + if (type_is_invalid(dest_type)) + return ira->codegen->invalid_instruction; + + if (get_codegen_ptr_type(dest_type) != nullptr) { + ir_add_error(ira, result_loc->source_instruction, + buf_sprintf("unable to @bitCast to pointer type '%s'", buf_ptr(&dest_type->name))); + return ira->codegen->invalid_instruction; + } + + if (!type_can_bit_cast(dest_type)) { + ir_add_error(ira, result_loc->source_instruction, + buf_sprintf("unable to @bitCast to type '%s'", buf_ptr(&dest_type->name))); + return ira->codegen->invalid_instruction; + } + + if (get_codegen_ptr_type(value_type) != nullptr) { + ir_add_error(ira, suspend_source_instr, + buf_sprintf("unable to @bitCast from pointer type '%s'", buf_ptr(&value_type->name))); + return ira->codegen->invalid_instruction; + } + + if (!type_can_bit_cast(value_type)) { + ir_add_error(ira, suspend_source_instr, + buf_sprintf("unable to @bitCast from type '%s'", buf_ptr(&value_type->name))); + return ira->codegen->invalid_instruction; + } + + + IrInstruction *parent_result_loc = ir_resolve_result(ira, suspend_source_instr, result_bit_cast->parent, + dest_type, nullptr); + if (parent_result_loc == nullptr || type_is_invalid(parent_result_loc->value.type) || + parent_result_loc->value.type->id == ZigTypeIdUnreachable) + { + return parent_result_loc; + } + ZigType *ptr_type = get_pointer_to_type(ira->codegen, value_type, false); + result_loc->written = true; + result_loc->resolved_loc = ir_analyze_ptr_cast(ira, suspend_source_instr, parent_result_loc, + ptr_type, result_bit_cast->base.source_instruction, false); + return result_loc->resolved_loc; + } } zig_unreachable(); } @@ -22755,28 +22810,6 @@ static Error buf_read_value_bytes(IrAnalyze *ira, CodeGen *codegen, AstNode *sou zig_unreachable(); } -static bool type_can_bit_cast(ZigType *t) { - switch (t->id) { - case ZigTypeIdInvalid: - zig_unreachable(); - case ZigTypeIdMetaType: - case ZigTypeIdOpaque: - case ZigTypeIdBoundFn: - case ZigTypeIdArgTuple: - case ZigTypeIdUnreachable: - case ZigTypeIdComptimeFloat: - case ZigTypeIdComptimeInt: - case ZigTypeIdEnumLiteral: - case ZigTypeIdUndefined: - case ZigTypeIdNull: - case ZigTypeIdPointer: - return false; - default: - // TODO list these types out explicitly, there are probably some other invalid ones here - return true; - } -} - static IrInstruction *ir_analyze_bit_cast(IrAnalyze *ira, IrInstruction *source_instr, IrInstruction *value, ZigType *dest_type) { @@ -22829,50 +22862,10 @@ static IrInstruction *ir_analyze_bit_cast(IrAnalyze *ira, IrInstruction *source_ } IrInstruction *result = ir_build_bit_cast_gen(ira, source_instr, value, dest_type); - if (handle_is_ptr(dest_type) && !handle_is_ptr(src_type)) { - ir_add_alloca(ira, result, dest_type); - } + assert(!(handle_is_ptr(dest_type) && !handle_is_ptr(src_type))); return result; } -static IrInstruction *ir_analyze_instruction_bit_cast(IrAnalyze *ira, IrInstructionBitCast *instruction) { - IrInstruction *dest_type_value = instruction->dest_type->child; - ZigType *dest_type = ir_resolve_type(ira, dest_type_value); - if (type_is_invalid(dest_type)) - return ira->codegen->invalid_instruction; - - IrInstruction *value = instruction->value->child; - ZigType *src_type = value->value.type; - if (type_is_invalid(src_type)) - return ira->codegen->invalid_instruction; - - if (get_codegen_ptr_type(src_type) != nullptr) { - ir_add_error(ira, value, - buf_sprintf("unable to @bitCast from pointer type '%s'", buf_ptr(&src_type->name))); - return ira->codegen->invalid_instruction; - } - - if (!type_can_bit_cast(src_type)) { - ir_add_error(ira, dest_type_value, - buf_sprintf("unable to @bitCast from type '%s'", buf_ptr(&src_type->name))); - return ira->codegen->invalid_instruction; - } - - if (get_codegen_ptr_type(dest_type) != nullptr) { - ir_add_error(ira, dest_type_value, - buf_sprintf("unable to @bitCast to pointer type '%s'", buf_ptr(&dest_type->name))); - return ira->codegen->invalid_instruction; - } - - if (!type_can_bit_cast(dest_type)) { - ir_add_error(ira, dest_type_value, - buf_sprintf("unable to @bitCast to type '%s'", buf_ptr(&dest_type->name))); - return ira->codegen->invalid_instruction; - } - - return ir_analyze_bit_cast(ira, &instruction->base, value, dest_type); -} - static IrInstruction *ir_analyze_int_to_ptr(IrAnalyze *ira, IrInstruction *source_instr, IrInstruction *target, ZigType *ptr_type) { @@ -24089,8 +24082,6 @@ static IrInstruction *ir_analyze_instruction_base(IrAnalyze *ira, IrInstruction return ir_analyze_instruction_panic(ira, (IrInstructionPanic *)instruction); case IrInstructionIdPtrCastSrc: return ir_analyze_instruction_ptr_cast(ira, (IrInstructionPtrCastSrc *)instruction); - case IrInstructionIdBitCast: - return ir_analyze_instruction_bit_cast(ira, (IrInstructionBitCast *)instruction); case IrInstructionIdIntToPtr: return ir_analyze_instruction_int_to_ptr(ira, (IrInstructionIntToPtr *)instruction); case IrInstructionIdPtrToInt: @@ -24386,7 +24377,6 @@ bool ir_has_side_effects(IrInstruction *instruction) { case IrInstructionIdTestComptime: case IrInstructionIdPtrCastSrc: case IrInstructionIdPtrCastGen: - case IrInstructionIdBitCast: case IrInstructionIdBitCastGen: case IrInstructionIdWidenOrShorten: case IrInstructionIdPtrToInt: diff --git a/src/ir_print.cpp b/src/ir_print.cpp index 42b93aec4..925d802e6 100644 --- a/src/ir_print.cpp +++ b/src/ir_print.cpp @@ -219,6 +219,12 @@ static void ir_print_result_loc_peer(IrPrint *irp, ResultLocPeer *result_loc_pee fprintf(irp->f, ")"); } +static void ir_print_result_loc_bit_cast(IrPrint *irp, ResultLocBitCast *result_loc_bit_cast) { + fprintf(irp->f, "bitcast(ty="); + ir_print_other_instruction(irp, result_loc_bit_cast->base.source_instruction); + fprintf(irp->f, ")"); +} + static void ir_print_result_loc(IrPrint *irp, ResultLoc *result_loc) { switch (result_loc->id) { case ResultLocIdInvalid: @@ -235,6 +241,8 @@ static void ir_print_result_loc(IrPrint *irp, ResultLoc *result_loc) { return ir_print_result_loc_instruction(irp, (ResultLocInstruction *)result_loc); case ResultLocIdPeer: return ir_print_result_loc_peer(irp, (ResultLocPeer *)result_loc); + case ResultLocIdBitCast: + return ir_print_result_loc_bit_cast(irp, (ResultLocBitCast *)result_loc); case ResultLocIdPeerParent: fprintf(irp->f, "peer_parent"); return; @@ -1011,14 +1019,6 @@ static void ir_print_ptr_cast_gen(IrPrint *irp, IrInstructionPtrCastGen *instruc fprintf(irp->f, ")"); } -static void ir_print_bit_cast(IrPrint *irp, IrInstructionBitCast *instruction) { - fprintf(irp->f, "@bitCast("); - ir_print_other_instruction(irp, instruction->dest_type); - fprintf(irp->f, ","); - ir_print_other_instruction(irp, instruction->value); - fprintf(irp->f, ")"); -} - static void ir_print_bit_cast_gen(IrPrint *irp, IrInstructionBitCastGen *instruction) { fprintf(irp->f, "@bitCast("); ir_print_other_instruction(irp, instruction->operand); @@ -1818,9 +1818,6 @@ static void ir_print_instruction(IrPrint *irp, IrInstruction *instruction) { case IrInstructionIdPtrCastGen: ir_print_ptr_cast_gen(irp, (IrInstructionPtrCastGen *)instruction); break; - case IrInstructionIdBitCast: - ir_print_bit_cast(irp, (IrInstructionBitCast *)instruction); - break; case IrInstructionIdBitCastGen: ir_print_bit_cast_gen(irp, (IrInstructionBitCastGen *)instruction); break;