motiejus/zig
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add integer wrapping

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see #46
This commit is contained in:
Andrew Kelley
2016-05-05 17:19:01 -07:00
parent dedde0d790
commit 094336f07c
7 changed files with 155 additions and 78 deletions
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175
src/codegen.cpp
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@@ -338,6 +338,11 @@ static bool want_debug_safety(CodeGen *g, AstNode *node) {
return !g->is_release_build && !node->block_context->safety_off;
}
static void gen_debug_safety_crash(CodeGen *g) {
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
LLVMBuildUnreachable(g->builder);
}
static void add_bounds_check(CodeGen *g, AstNode *source_node, LLVMValueRef target_val,
LLVMIntPredicate lower_pred, LLVMValueRef lower_value,
LLVMIntPredicate upper_pred, LLVMValueRef upper_value)
@@ -362,8 +367,7 @@ static void add_bounds_check(CodeGen *g, AstNode *source_node, LLVMValueRef targ
LLVMBuildCondBr(g->builder, lower_ok_val, lower_ok_block, bounds_check_fail_block);
LLVMPositionBuilderAtEnd(g->builder, bounds_check_fail_block);
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
LLVMBuildUnreachable(g->builder);
gen_debug_safety_crash(g);
if (upper_value) {
LLVMPositionBuilderAtEnd(g->builder, lower_ok_block);
@@ -1369,8 +1373,7 @@ static LLVMValueRef gen_prefix_op_expr(CodeGen *g, AstNode *node) {
LLVMBuildCondBr(g->builder, cond_val, ok_block, err_block);
LLVMPositionBuilderAtEnd(g->builder, err_block);
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
LLVMBuildUnreachable(g->builder);
gen_debug_safety_crash(g);
LLVMPositionBuilderAtEnd(g->builder, ok_block);
}
@@ -1408,8 +1411,7 @@ static LLVMValueRef gen_prefix_op_expr(CodeGen *g, AstNode *node) {
LLVMBuildCondBr(g->builder, cond_val, ok_block, null_block);
LLVMPositionBuilderAtEnd(g->builder, null_block);
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
LLVMBuildUnreachable(g->builder);
gen_debug_safety_crash(g);
LLVMPositionBuilderAtEnd(g->builder, ok_block);
}
@@ -1429,6 +1431,28 @@ static LLVMValueRef gen_prefix_op_expr(CodeGen *g, AstNode *node) {
zig_unreachable();
}
static LLVMValueRef gen_overflow_op(CodeGen *g, TypeTableEntry *type_entry, AddSubMul op,
LLVMValueRef val1, LLVMValueRef val2)
{
LLVMValueRef fn_val = get_int_overflow_fn(g, type_entry, op);
LLVMValueRef params[] = {
val1,
val2,
};
LLVMValueRef result_struct = LLVMBuildCall(g->builder, fn_val, params, 2, "");
LLVMValueRef result = LLVMBuildExtractValue(g->builder, result_struct, 0, "");
LLVMValueRef overflow_bit = LLVMBuildExtractValue(g->builder, result_struct, 1, "");
LLVMBasicBlockRef fail_block = LLVMAppendBasicBlock(g->cur_fn->fn_value, "OverflowFail");
LLVMBasicBlockRef ok_block = LLVMAppendBasicBlock(g->cur_fn->fn_value, "OverflowOk");
LLVMBuildCondBr(g->builder, overflow_bit, fail_block, ok_block);
LLVMPositionBuilderAtEnd(g->builder, fail_block);
gen_debug_safety_crash(g);
LLVMPositionBuilderAtEnd(g->builder, ok_block);
return result;
}
static LLVMValueRef gen_arithmetic_bin_op(CodeGen *g, AstNode *source_node,
LLVMValueRef val1, LLVMValueRef val2,
TypeTableEntry *op1_type, TypeTableEntry *op2_type,
@@ -1469,24 +1493,54 @@ static LLVMValueRef gen_arithmetic_bin_op(CodeGen *g, AstNode *source_node,
set_debug_source_node(g, source_node);
if (op1_type->id == TypeTableEntryIdFloat) {
return LLVMBuildFAdd(g->builder, val1, val2, "");
} else if (op1_type->id == TypeTableEntryIdInt) {
if (op1_type->data.integral.is_wrapping) {
return LLVMBuildAdd(g->builder, val1, val2, "");
} else if (want_debug_safety(g, source_node)) {
return gen_overflow_op(g, op1_type, AddSubMulAdd, val1, val2);
} else if (op1_type->data.integral.is_signed) {
return LLVMBuildNSWAdd(g->builder, val1, val2, "");
} else {
return LLVMBuildNUWAdd(g->builder, val1, val2, "");
}
} else {
return LLVMBuildAdd(g->builder, val1, val2, "");
zig_unreachable();
}
case BinOpTypeSub:
case BinOpTypeAssignMinus:
set_debug_source_node(g, source_node);
if (op1_type->id == TypeTableEntryIdFloat) {
return LLVMBuildFSub(g->builder, val1, val2, "");
} else if (op1_type->id == TypeTableEntryIdInt) {
if (op1_type->data.integral.is_wrapping) {
return LLVMBuildSub(g->builder, val1, val2, "");
} else if (want_debug_safety(g, source_node)) {
return gen_overflow_op(g, op1_type, AddSubMulSub, val1, val2);
} else if (op1_type->data.integral.is_signed) {
return LLVMBuildNSWSub(g->builder, val1, val2, "");
} else {
return LLVMBuildNUWSub(g->builder, val1, val2, "");
}
} else {
return LLVMBuildSub(g->builder, val1, val2, "");
zig_unreachable();
}
case BinOpTypeMult:
case BinOpTypeAssignTimes:
set_debug_source_node(g, source_node);
if (op1_type->id == TypeTableEntryIdFloat) {
return LLVMBuildFMul(g->builder, val1, val2, "");
} else if (op1_type->id == TypeTableEntryIdInt) {
if (op1_type->data.integral.is_wrapping) {
return LLVMBuildMul(g->builder, val1, val2, "");
} else if (want_debug_safety(g, source_node)) {
return gen_overflow_op(g, op1_type, AddSubMulMul, val1, val2);
} else if (op1_type->data.integral.is_signed) {
return LLVMBuildNSWMul(g->builder, val1, val2, "");
} else {
return LLVMBuildNUWMul(g->builder, val1, val2, "");
}
} else {
return LLVMBuildMul(g->builder, val1, val2, "");
zig_unreachable();
}
case BinOpTypeDiv:
case BinOpTypeAssignDiv:
@@ -2472,9 +2526,10 @@ static LLVMValueRef gen_container_init_expr(CodeGen *g, AstNode *node) {
assert(node->data.container_init_expr.entries.length == 0);
set_debug_source_node(g, node);
if (want_debug_safety(g, node)) {
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
gen_debug_safety_crash(g);
} else {
LLVMBuildUnreachable(g->builder);
}
LLVMBuildUnreachable(g->builder);
return nullptr;
} else if (type_entry->id == TypeTableEntryIdVoid) {
assert(node->data.container_init_expr.entries.length == 0);
@@ -2983,7 +3038,7 @@ static LLVMValueRef gen_switch_expr(CodeGen *g, AstNode *node) {
set_debug_source_node(g, prong_expr);
LLVMBuildBr(g->builder, end_block);
incoming_values.append(prong_val);
incoming_blocks.append(prong_block);
incoming_blocks.append(LLVMGetInsertBlock(g->builder));
}
}
@@ -2991,9 +3046,10 @@ static LLVMValueRef gen_switch_expr(CodeGen *g, AstNode *node) {
LLVMPositionBuilderAtEnd(g->builder, else_block);
set_debug_source_node(g, node);
if (want_debug_safety(g, node)) {
LLVMBuildCall(g->builder, g->trap_fn_val, nullptr, 0, "");
gen_debug_safety_crash(g);
} else {
LLVMBuildUnreachable(g->builder);
}
LLVMBuildUnreachable(g->builder);
}
if (end_unreachable) {
@@ -3776,6 +3832,18 @@ static const CIntTypeInfo c_int_type_infos[] = {
{CIntTypeULongLong, "c_ulonglong", false},
};
struct SignWrap {
bool is_signed;
bool is_wrapping;
};
static const SignWrap sign_wrap_list[] = {
{false, false},
{false, true},
{true, false},
{true, true},
};
static void define_builtin_types(CodeGen *g) {
{
// if this type is anywhere in the AST, we should never hit codegen.
@@ -3812,17 +3880,20 @@ static void define_builtin_types(CodeGen *g) {
g->builtin_types.entry_undef = entry;
}
for (int i = 0; i < array_length(int_sizes_in_bits); i += 1) {
int size_in_bits = int_sizes_in_bits[i];
bool is_signed = true;
for (;;) {
for (int int_size_i = 0; int_size_i < array_length(int_sizes_in_bits); int_size_i += 1) {
int size_in_bits = int_sizes_in_bits[int_size_i];
for (int sign_wrap_i = 0; sign_wrap_i < array_length(sign_wrap_list); sign_wrap_i += 1) {
bool is_signed = sign_wrap_list[sign_wrap_i].is_signed;
bool is_wrapping = sign_wrap_list[sign_wrap_i].is_wrapping;
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdInt);
entry->type_ref = LLVMIntType(size_in_bits);
entry->deep_const = true;
const char u_or_i = is_signed ? 'i' : 'u';
const char *w_or_none = is_wrapping ? "w" : "";
buf_resize(&entry->name, 0);
buf_appendf(&entry->name, "%c%d", u_or_i, size_in_bits);
buf_appendf(&entry->name, "%c%d%s", u_or_i, size_in_bits, w_or_none);
unsigned dwarf_tag;
if (is_signed) {
@@ -3844,16 +3915,11 @@ static void define_builtin_types(CodeGen *g) {
entry->di_type = LLVMZigCreateDebugBasicType(g->dbuilder, buf_ptr(&entry->name),
debug_size_in_bits, debug_align_in_bits, dwarf_tag);
entry->data.integral.is_signed = is_signed;
entry->data.integral.is_wrapping = is_wrapping;
entry->data.integral.bit_count = size_in_bits;
g->primitive_type_table.put(&entry->name, entry);
get_int_type_ptr(g, is_signed, size_in_bits)[0] = entry;
if (!is_signed) {
break;
} else {
is_signed = false;
}
get_int_type_ptr(g, is_signed, is_wrapping, size_in_bits)[0] = entry;
}
}
@@ -3875,6 +3941,7 @@ static void define_builtin_types(CodeGen *g) {
debug_align_in_bits,
is_signed ? LLVMZigEncoding_DW_ATE_signed() : LLVMZigEncoding_DW_ATE_unsigned());
entry->data.integral.is_signed = is_signed;
entry->data.integral.is_wrapping = !is_signed;
entry->data.integral.bit_count = size_in_bits;
g->primitive_type_table.put(&entry->name, entry);
@@ -3895,12 +3962,22 @@ static void define_builtin_types(CodeGen *g) {
g->builtin_types.entry_bool = entry;
g->primitive_type_table.put(&entry->name, entry);
}
{
for (int sign_wrap_i = 0; sign_wrap_i < array_length(sign_wrap_list); sign_wrap_i += 1) {
bool is_signed = sign_wrap_list[sign_wrap_i].is_signed;
bool is_wrapping = sign_wrap_list[sign_wrap_i].is_wrapping;
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdInt);
entry->deep_const = true;
entry->type_ref = LLVMIntType(g->pointer_size_bytes * 8);
buf_init_from_str(&entry->name, "isize");
entry->data.integral.is_signed = true;
const char u_or_i = is_signed ? 'i' : 'u';
const char *w_or_none = is_wrapping ? "w" : "";
buf_resize(&entry->name, 0);
buf_appendf(&entry->name, "%csize%s", u_or_i, w_or_none);
entry->data.integral.is_signed = is_signed;
entry->data.integral.is_wrapping = is_wrapping;
entry->data.integral.bit_count = g->pointer_size_bytes * 8;
uint64_t debug_size_in_bits = 8*LLVMStoreSizeOfType(g->target_data_ref, entry->type_ref);
@@ -3908,26 +3985,14 @@ static void define_builtin_types(CodeGen *g) {
entry->di_type = LLVMZigCreateDebugBasicType(g->dbuilder, buf_ptr(&entry->name),
debug_size_in_bits,
debug_align_in_bits,
LLVMZigEncoding_DW_ATE_signed());
g->builtin_types.entry_isize = entry;
is_signed ? LLVMZigEncoding_DW_ATE_signed() : LLVMZigEncoding_DW_ATE_unsigned());
g->primitive_type_table.put(&entry->name, entry);
}
{
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdInt);
entry->deep_const = true;
entry->type_ref = LLVMIntType(g->pointer_size_bytes * 8);
buf_init_from_str(&entry->name, "usize");
entry->data.integral.is_signed = false;
entry->data.integral.bit_count = g->pointer_size_bytes * 8;
uint64_t debug_size_in_bits = 8*LLVMStoreSizeOfType(g->target_data_ref, entry->type_ref);
uint64_t debug_align_in_bits = 8*LLVMABISizeOfType(g->target_data_ref, entry->type_ref);
entry->di_type = LLVMZigCreateDebugBasicType(g->dbuilder, buf_ptr(&entry->name),
debug_size_in_bits,
debug_align_in_bits,
LLVMZigEncoding_DW_ATE_unsigned());
g->builtin_types.entry_usize = entry;
g->primitive_type_table.put(&entry->name, entry);
if (is_signed && !is_wrapping) {
g->builtin_types.entry_isize = entry;
} else if (!is_signed && !is_wrapping) {
g->builtin_types.entry_usize = entry;
}
}
{
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdFloat);
@@ -4009,14 +4074,14 @@ static void define_builtin_types(CodeGen *g) {
g->primitive_type_table.put(&entry->name, entry);
}
g->builtin_types.entry_u8 = get_int_type(g, false, 8);
g->builtin_types.entry_u16 = get_int_type(g, false, 16);
g->builtin_types.entry_u32 = get_int_type(g, false, 32);
g->builtin_types.entry_u64 = get_int_type(g, false, 64);
g->builtin_types.entry_i8 = get_int_type(g, true, 8);
g->builtin_types.entry_i16 = get_int_type(g, true, 16);
g->builtin_types.entry_i32 = get_int_type(g, true, 32);
g->builtin_types.entry_i64 = get_int_type(g, true, 64);
g->builtin_types.entry_u8 = get_int_type(g, false, false, 8);
g->builtin_types.entry_u16 = get_int_type(g, false, false, 16);
g->builtin_types.entry_u32 = get_int_type(g, false, false, 32);
g->builtin_types.entry_u64 = get_int_type(g, false, false, 64);
g->builtin_types.entry_i8 = get_int_type(g, true, false, 8);
g->builtin_types.entry_i16 = get_int_type(g, true, false, 16);
g->builtin_types.entry_i32 = get_int_type(g, true, false, 32);
g->builtin_types.entry_i64 = get_int_type(g, true, false, 64);
{
g->builtin_types.entry_c_void = get_typedecl_type(g, "c_void", g->builtin_types.entry_u8);