From c36289511629e01bbd32bc5f1133f5ed5997d1e0 Mon Sep 17 00:00:00 2001 From: Andrew Kelley Date: Mon, 10 Jun 2019 15:49:45 -0400 Subject: result location semantics for slices ```zig export fn entry() void { var buf: [10]u8 = undefined; const slice1: []const u8 = &buf; const slice2 = buf[0..]; } ``` ```llvm define void @entry() #2 !dbg !35 { Entry: %buf = alloca [10 x i8], align 1 %slice1 = alloca %"[]u8", align 8 %slice2 = alloca %"[]u8", align 8 %0 = bitcast [10 x i8]* %buf to i8*, !dbg !46 call void @llvm.memset.p0i8.i64(i8* align 1 %0, i8 -86, i64 10, i1 false), !dbg !46 call void @llvm.dbg.declare(metadata [10 x i8]* %buf, metadata !39, metadata !DIExpression()), !dbg !46 %1 = getelementptr inbounds %"[]u8", %"[]u8"* %slice1, i32 0, i32 0, !dbg !47 %2 = getelementptr inbounds [10 x i8], [10 x i8]* %buf, i64 0, i64 0, !dbg !47 store i8* %2, i8** %1, align 8, !dbg !47 %3 = getelementptr inbounds %"[]u8", %"[]u8"* %slice1, i32 0, i32 1, !dbg !47 store i64 10, i64* %3, align 8, !dbg !47 call void @llvm.dbg.declare(metadata %"[]u8"* %slice1, metadata !44, metadata !DIExpression()), !dbg !48 %4 = getelementptr inbounds %"[]u8", %"[]u8"* %slice2, i32 0, i32 0, !dbg !49 %5 = getelementptr inbounds [10 x i8], [10 x i8]* %buf, i64 0, i64 0, !dbg !49 store i8* %5, i8** %4, align 8, !dbg !49 %6 = getelementptr inbounds %"[]u8", %"[]u8"* %slice2, i32 0, i32 1, !dbg !49 store i64 10, i64* %6, align 8, !dbg !49 call void @llvm.dbg.declare(metadata %"[]u8"* %slice2, metadata !45, metadata !DIExpression()), !dbg !50 ret void, !dbg !51 } ``` --- src/codegen.cpp | 72 +++++++++++++++++++++++++++++++-------------------------- 1 file changed, 39 insertions(+), 33 deletions(-) (limited to 'src/codegen.cpp') diff --git a/src/codegen.cpp b/src/codegen.cpp index 894d22d471..f748c575b0 100644 --- a/src/codegen.cpp +++ b/src/codegen.cpp @@ -3072,33 +3072,39 @@ static LLVMValueRef ir_render_cast(CodeGen *g, IrExecutable *executable, return expr_val; case CastOpBitCast: return LLVMBuildBitCast(g->builder, expr_val, get_llvm_type(g, wanted_type), ""); - case CastOpPtrOfArrayToSlice: { - assert(cast_instruction->tmp_ptr); - assert(actual_type->id == ZigTypeIdPointer); - ZigType *array_type = actual_type->data.pointer.child_type; - assert(array_type->id == ZigTypeIdArray); - - LLVMValueRef ptr_field_ptr = LLVMBuildStructGEP(g->builder, cast_instruction->tmp_ptr, - slice_ptr_index, ""); - LLVMValueRef indices[] = { - LLVMConstNull(g->builtin_types.entry_usize->llvm_type), - LLVMConstInt(g->builtin_types.entry_usize->llvm_type, 0, false), - }; - LLVMValueRef slice_start_ptr = LLVMBuildInBoundsGEP(g->builder, expr_val, indices, 2, ""); - gen_store_untyped(g, slice_start_ptr, ptr_field_ptr, 0, false); - - LLVMValueRef len_field_ptr = LLVMBuildStructGEP(g->builder, cast_instruction->tmp_ptr, - slice_len_index, ""); - LLVMValueRef len_value = LLVMConstInt(g->builtin_types.entry_usize->llvm_type, - array_type->data.array.len, false); - gen_store_untyped(g, len_value, len_field_ptr, 0, false); - - return cast_instruction->tmp_ptr; - } } zig_unreachable(); } +static LLVMValueRef ir_render_ptr_of_array_to_slice(CodeGen *g, IrExecutable *executable, + IrInstructionPtrOfArrayToSlice *instruction) +{ + ZigType *actual_type = instruction->operand->value.type; + LLVMValueRef expr_val = ir_llvm_value(g, instruction->operand); + assert(expr_val); + + LLVMValueRef result_loc = ir_llvm_value(g, instruction->result_loc); + + assert(actual_type->id == ZigTypeIdPointer); + ZigType *array_type = actual_type->data.pointer.child_type; + assert(array_type->id == ZigTypeIdArray); + + LLVMValueRef ptr_field_ptr = LLVMBuildStructGEP(g->builder, result_loc, slice_ptr_index, ""); + LLVMValueRef indices[] = { + LLVMConstNull(g->builtin_types.entry_usize->llvm_type), + LLVMConstInt(g->builtin_types.entry_usize->llvm_type, 0, false), + }; + LLVMValueRef slice_start_ptr = LLVMBuildInBoundsGEP(g->builder, expr_val, indices, 2, ""); + gen_store_untyped(g, slice_start_ptr, ptr_field_ptr, 0, false); + + LLVMValueRef len_field_ptr = LLVMBuildStructGEP(g->builder, result_loc, slice_len_index, ""); + LLVMValueRef len_value = LLVMConstInt(g->builtin_types.entry_usize->llvm_type, + array_type->data.array.len, false); + gen_store_untyped(g, len_value, len_field_ptr, 0, false); + + return result_loc; +} + static LLVMValueRef ir_render_ptr_cast(CodeGen *g, IrExecutable *executable, IrInstructionPtrCastGen *instruction) { @@ -4603,16 +4609,14 @@ static LLVMValueRef ir_render_memcpy(CodeGen *g, IrExecutable *executable, IrIns return nullptr; } -static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInstructionSlice *instruction) { - assert(instruction->tmp_ptr); - +static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInstructionSliceGen *instruction) { LLVMValueRef array_ptr_ptr = ir_llvm_value(g, instruction->ptr); ZigType *array_ptr_type = instruction->ptr->value.type; assert(array_ptr_type->id == ZigTypeIdPointer); ZigType *array_type = array_ptr_type->data.pointer.child_type; LLVMValueRef array_ptr = get_handle_value(g, array_ptr_ptr, array_type, array_ptr_type); - LLVMValueRef tmp_struct_ptr = instruction->tmp_ptr; + LLVMValueRef tmp_struct_ptr = ir_llvm_value(g, instruction->result_loc); bool want_runtime_safety = instruction->safety_check_on && ir_want_runtime_safety(g, &instruction->base); @@ -4630,7 +4634,9 @@ static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInst end_val = LLVMConstInt(g->builtin_types.entry_usize->llvm_type, array_type->data.array.len, false); } if (want_runtime_safety) { - add_bounds_check(g, start_val, LLVMIntEQ, nullptr, LLVMIntULE, end_val); + if (instruction->start->value.special == ConstValSpecialRuntime || instruction->end) { + add_bounds_check(g, start_val, LLVMIntEQ, nullptr, LLVMIntULE, end_val); + } if (instruction->end) { LLVMValueRef array_end = LLVMConstInt(g->builtin_types.entry_usize->llvm_type, array_type->data.array.len, false); @@ -5525,6 +5531,7 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable, case IrInstructionIdImplicitCast: case IrInstructionIdResolveResult: case IrInstructionIdContainerInitList: + case IrInstructionIdSliceSrc: zig_unreachable(); case IrInstructionIdDeclVarGen: @@ -5595,8 +5602,8 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable, return ir_render_memset(g, executable, (IrInstructionMemset *)instruction); case IrInstructionIdMemcpy: return ir_render_memcpy(g, executable, (IrInstructionMemcpy *)instruction); - case IrInstructionIdSlice: - return ir_render_slice(g, executable, (IrInstructionSlice *)instruction); + case IrInstructionIdSliceGen: + return ir_render_slice(g, executable, (IrInstructionSliceGen *)instruction); case IrInstructionIdBreakpoint: return ir_render_breakpoint(g, executable, (IrInstructionBreakpoint *)instruction); case IrInstructionIdReturnAddress: @@ -5697,6 +5704,8 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable, return ir_render_assert_non_null(g, executable, (IrInstructionAssertNonNull *)instruction); case IrInstructionIdResizeSlice: return ir_render_resize_slice(g, executable, (IrInstructionResizeSlice *)instruction); + case IrInstructionIdPtrOfArrayToSlice: + return ir_render_ptr_of_array_to_slice(g, executable, (IrInstructionPtrOfArrayToSlice *)instruction); } zig_unreachable(); } @@ -6831,9 +6840,6 @@ 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 == IrInstructionIdSlice) { - IrInstructionSlice *slice_instruction = (IrInstructionSlice *)instruction; - slot = &slice_instruction->tmp_ptr; } else if (instruction->id == IrInstructionIdOptionalWrap) { IrInstructionOptionalWrap *maybe_wrap_instruction = (IrInstructionOptionalWrap *)instruction; slot = &maybe_wrap_instruction->tmp_ptr; -- cgit v1.2.3