diff --git a/src/codegen.cpp b/src/codegen.cpp index 54e9c44f9..c5fd87598 100644 --- a/src/codegen.cpp +++ b/src/codegen.cpp @@ -296,6 +296,7 @@ static LLVMValueRef gen_const_val(CodeGen *g, ConstExprValue *const_val, const c static void generate_error_name_table(CodeGen *g); static bool value_is_all_undef(ConstExprValue *const_val); static void gen_undef_init(CodeGen *g, uint32_t ptr_align_bytes, ZigType *value_type, LLVMValueRef ptr); +static LLVMValueRef build_alloca(CodeGen *g, ZigType *type_entry, const char *name, uint32_t alignment); static void addLLVMAttr(LLVMValueRef val, LLVMAttributeIndex attr_index, const char *attr_name) { unsigned kind_id = LLVMGetEnumAttributeKindForName(attr_name, strlen(attr_name)); @@ -1518,53 +1519,12 @@ static LLVMValueRef get_safety_crash_err_fn(CodeGen *g) { generate_error_name_table(g); assert(g->err_name_table != nullptr); - size_t unwrap_err_msg_text_len = strlen(unwrap_err_msg_text); - size_t err_buf_len = strlen(unwrap_err_msg_text) + g->largest_err_name_len; - LLVMValueRef *err_buf_vals = allocate(err_buf_len); - size_t i = 0; - for (; i < unwrap_err_msg_text_len; i += 1) { - err_buf_vals[i] = LLVMConstInt(LLVMInt8Type(), unwrap_err_msg_text[i], false); - } - for (; i < err_buf_len; i += 1) { - err_buf_vals[i] = LLVMGetUndef(LLVMInt8Type()); - } - uint32_t u8_align_bytes = get_abi_alignment(g, g->builtin_types.entry_u8); - LLVMValueRef init_value = LLVMConstArray(LLVMInt8Type(), err_buf_vals, err_buf_len); - LLVMValueRef global_array = LLVMAddGlobal(g->module, LLVMTypeOf(init_value), ""); - LLVMSetInitializer(global_array, init_value); - LLVMSetLinkage(global_array, LLVMInternalLinkage); - LLVMSetGlobalConstant(global_array, false); - LLVMSetUnnamedAddr(global_array, true); - LLVMSetAlignment(global_array, u8_align_bytes); - - ZigType *usize = g->builtin_types.entry_usize; - LLVMValueRef full_buf_ptr_indices[] = { - LLVMConstNull(usize->llvm_type), - LLVMConstNull(usize->llvm_type), - }; - LLVMValueRef full_buf_ptr = LLVMConstInBoundsGEP(global_array, full_buf_ptr_indices, 2); - - - ZigType *u8_ptr_type = get_pointer_to_type_extra(g, g->builtin_types.entry_u8, true, false, - PtrLenUnknown, get_abi_alignment(g, g->builtin_types.entry_u8), 0, 0, false); - ZigType *str_type = get_slice_type(g, u8_ptr_type); - LLVMValueRef global_slice_fields[] = { - full_buf_ptr, - LLVMConstNull(usize->llvm_type), - }; - LLVMValueRef slice_init_value = LLVMConstNamedStruct(get_llvm_type(g, str_type), global_slice_fields, 2); - LLVMValueRef global_slice = LLVMAddGlobal(g->module, LLVMTypeOf(slice_init_value), ""); - LLVMSetInitializer(global_slice, slice_init_value); - LLVMSetLinkage(global_slice, LLVMInternalLinkage); - LLVMSetGlobalConstant(global_slice, false); - LLVMSetUnnamedAddr(global_slice, true); - LLVMSetAlignment(global_slice, get_abi_alignment(g, str_type)); - - LLVMValueRef offset_ptr_indices[] = { - LLVMConstNull(usize->llvm_type), - LLVMConstInt(usize->llvm_type, unwrap_err_msg_text_len, false), - }; - LLVMValueRef offset_buf_ptr = LLVMConstInBoundsGEP(global_array, offset_ptr_indices, 2); + // Generate the constant part of the error message + LLVMValueRef msg_prefix_init = LLVMConstString(unwrap_err_msg_text, strlen(unwrap_err_msg_text), 1); + LLVMValueRef msg_prefix = LLVMAddGlobal(g->module, LLVMTypeOf(msg_prefix_init), ""); + LLVMSetInitializer(msg_prefix, msg_prefix_init); + LLVMSetLinkage(msg_prefix, LLVMInternalLinkage); + LLVMSetGlobalConstant(msg_prefix, true); Buf *fn_name = get_mangled_name(g, buf_create_from_str("__zig_fail_unwrap"), false); LLVMTypeRef fn_type_ref; @@ -1601,6 +1561,19 @@ static LLVMValueRef get_safety_crash_err_fn(CodeGen *g) { LLVMPositionBuilderAtEnd(g->builder, entry_block); ZigLLVMClearCurrentDebugLocation(g->builder); + ZigType *usize_ty = g->builtin_types.entry_usize; + ZigType *u8_ptr_type = get_pointer_to_type_extra(g, g->builtin_types.entry_u8, true, false, + PtrLenUnknown, get_abi_alignment(g, g->builtin_types.entry_u8), 0, 0, false); + ZigType *str_type = get_slice_type(g, u8_ptr_type); + + // Allocate a buffer to hold the fully-formatted error message + const size_t err_buf_len = strlen(unwrap_err_msg_text) + g->largest_err_name_len; + LLVMValueRef max_msg_len = LLVMConstInt(usize_ty->llvm_type, err_buf_len, 0); + LLVMValueRef msg_buffer = LLVMBuildArrayAlloca(g->builder, LLVMInt8Type(), max_msg_len, "msg_buffer"); + + // Allocate a []u8 slice for the message + LLVMValueRef msg_slice = build_alloca(g, str_type, "msg_slice", 0); + LLVMValueRef err_ret_trace_arg; LLVMValueRef err_val; if (g->have_err_ret_tracing) { @@ -1611,8 +1584,9 @@ static LLVMValueRef get_safety_crash_err_fn(CodeGen *g) { err_val = LLVMGetParam(fn_val, 0); } + // Fetch the error name from the global table LLVMValueRef err_table_indices[] = { - LLVMConstNull(g->builtin_types.entry_usize->llvm_type), + LLVMConstNull(usize_ty->llvm_type), err_val, }; LLVMValueRef err_name_val = LLVMBuildInBoundsGEP(g->builder, g->err_name_table, err_table_indices, 2, ""); @@ -1623,15 +1597,38 @@ static LLVMValueRef get_safety_crash_err_fn(CodeGen *g) { LLVMValueRef len_field_ptr = LLVMBuildStructGEP(g->builder, err_name_val, slice_len_index, ""); LLVMValueRef err_name_len = gen_load_untyped(g, len_field_ptr, 0, false, ""); - ZigLLVMBuildMemCpy(g->builder, offset_buf_ptr, u8_align_bytes, err_name_ptr, u8_align_bytes, err_name_len, false); + LLVMValueRef msg_prefix_len = LLVMConstInt(usize_ty->llvm_type, strlen(unwrap_err_msg_text), false); + // Points to the beginning of msg_buffer + LLVMValueRef msg_buffer_ptr_indices[] = { + LLVMConstNull(usize_ty->llvm_type), + }; + LLVMValueRef msg_buffer_ptr = LLVMBuildInBoundsGEP(g->builder, msg_buffer, msg_buffer_ptr_indices, 1, ""); + // Points to the beginning of the constant prefix message + LLVMValueRef msg_prefix_ptr_indices[] = { + LLVMConstNull(usize_ty->llvm_type), + }; + LLVMValueRef msg_prefix_ptr = LLVMConstInBoundsGEP(msg_prefix, msg_prefix_ptr_indices, 1); - LLVMValueRef const_prefix_len = LLVMConstInt(LLVMTypeOf(err_name_len), strlen(unwrap_err_msg_text), false); - LLVMValueRef full_buf_len = LLVMBuildNUWAdd(g->builder, const_prefix_len, err_name_len, ""); + // Build the message using the prefix... + ZigLLVMBuildMemCpy(g->builder, msg_buffer_ptr, 1, msg_prefix_ptr, 1, msg_prefix_len, false); + // ..and append the error name + LLVMValueRef msg_buffer_ptr_after_indices[] = { + msg_prefix_len, + }; + LLVMValueRef msg_buffer_ptr_after = LLVMBuildInBoundsGEP(g->builder, msg_buffer, msg_buffer_ptr_after_indices, 1, ""); + ZigLLVMBuildMemCpy(g->builder, msg_buffer_ptr_after, 1, err_name_ptr, 1, err_name_len, false); - LLVMValueRef global_slice_len_field_ptr = LLVMBuildStructGEP(g->builder, global_slice, slice_len_index, ""); - gen_store(g, full_buf_len, global_slice_len_field_ptr, u8_ptr_type); + // Set the slice pointer + LLVMValueRef msg_slice_ptr_field_ptr = LLVMBuildStructGEP(g->builder, msg_slice, slice_ptr_index, ""); + gen_store_untyped(g, msg_buffer_ptr, msg_slice_ptr_field_ptr, 0, false); - gen_panic(g, global_slice, err_ret_trace_arg); + // Set the slice length + LLVMValueRef slice_len = LLVMBuildNUWAdd(g->builder, msg_prefix_len, err_name_len, ""); + LLVMValueRef msg_slice_len_field_ptr = LLVMBuildStructGEP(g->builder, msg_slice, slice_len_index, ""); + gen_store_untyped(g, slice_len, msg_slice_len_field_ptr, 0, false); + + // Call panic() + gen_panic(g, msg_slice, err_ret_trace_arg); LLVMPositionBuilderAtEnd(g->builder, prev_block); LLVMSetCurrentDebugLocation(g->builder, prev_debug_location);