Commit 4650e5b9fc
src/Sema.zig
@@ -33814,11 +33814,11 @@ fn cmpNumeric(
const maybe_lhs_val = try sema.resolveValue(lhs);
const maybe_rhs_val = try sema.resolveValue(rhs);
- // If the LHS is const, check if there is a guaranteed result which does not depend on ths RHS.
+ // If the LHS is const, check if there is a guaranteed result which does not depend on ths RHS value.
if (maybe_lhs_val) |lhs_val| {
// Result based on comparison exceeding type bounds
- if (!lhs_val.isUndef(zcu) and (lhs_ty.isInt(zcu) or lhs_ty_tag == .comptime_int) and rhs_ty.isInt(zcu)) {
- if (try sema.compareIntsOnlyPossibleResult(try sema.resolveLazyValue(lhs_val), op, rhs_ty)) |res| {
+ if (!lhs_val.isUndef(zcu) and (lhs_ty_tag == .int or lhs_ty_tag == .comptime_int) and rhs_ty.isInt(zcu)) {
+ if (try sema.compareIntsOnlyPossibleResult(lhs_val, op, rhs_ty)) |res| {
return if (res) .bool_true else .bool_false;
}
}
@@ -33826,13 +33826,20 @@ fn cmpNumeric(
if (lhs_val.isNan(zcu)) {
return if (op == .neq) .bool_true else .bool_false;
}
+ // Result based on inf comparison to int
+ if (lhs_val.isInf(zcu) and rhs_ty_tag == .int) return switch (op) {
+ .neq => .bool_true,
+ .eq => .bool_false,
+ .gt, .gte => if (lhs_val.isNegativeInf(zcu)) .bool_false else .bool_true,
+ .lt, .lte => if (lhs_val.isNegativeInf(zcu)) .bool_true else .bool_false,
+ };
}
- // If the RHS is const, check if there is a guaranteed result which does not depend on ths LHS.
+ // If the RHS is const, check if there is a guaranteed result which does not depend on ths LHS value.
if (maybe_rhs_val) |rhs_val| {
// Result based on comparison exceeding type bounds
- if (!rhs_val.isUndef(zcu) and (rhs_ty.isInt(zcu) or rhs_ty_tag == .comptime_int) and lhs_ty.isInt(zcu)) {
- if (try sema.compareIntsOnlyPossibleResult(try sema.resolveLazyValue(rhs_val), op.reverse(), lhs_ty)) |res| {
+ if (!rhs_val.isUndef(zcu) and (rhs_ty_tag == .int or rhs_ty_tag == .comptime_int) and lhs_ty.isInt(zcu)) {
+ if (try sema.compareIntsOnlyPossibleResult(rhs_val, op.reverse(), lhs_ty)) |res| {
return if (res) .bool_true else .bool_false;
}
}
@@ -33840,6 +33847,13 @@ fn cmpNumeric(
if (rhs_val.isNan(zcu)) {
return if (op == .neq) .bool_true else .bool_false;
}
+ // Result based on inf comparison to int
+ if (rhs_val.isInf(zcu) and lhs_ty_tag == .int) return switch (op) {
+ .neq => .bool_true,
+ .eq => .bool_false,
+ .gt, .gte => if (rhs_val.isNegativeInf(zcu)) .bool_true else .bool_false,
+ .lt, .lte => if (rhs_val.isNegativeInf(zcu)) .bool_false else .bool_true,
+ };
}
// Any other comparison depends on both values, so the result is undef if either is undef.
@@ -33889,17 +33903,18 @@ fn cmpNumeric(
const casted_rhs = try sema.coerce(block, dest_ty, rhs, rhs_src);
return block.addBinOp(Air.Inst.Tag.fromCmpOp(op, block.float_mode == .optimized), casted_lhs, casted_rhs);
}
+
// For mixed unsigned integer sizes, implicit cast both operands to the larger integer.
// For mixed signed and unsigned integers, implicit cast both operands to a signed
// integer with + 1 bit.
// For mixed floats and integers, extract the integer part from the float, cast that to
// a signed integer with mantissa bits + 1, and if there was any non-integral part of the float,
// add/subtract 1.
- const lhs_is_signed = if (try sema.resolveDefinedValue(block, lhs_src, lhs)) |lhs_val|
+ const lhs_is_signed = if (maybe_lhs_val) |lhs_val|
!(try lhs_val.compareAllWithZeroSema(.gte, pt))
else
(lhs_ty.isRuntimeFloat() or lhs_ty.isSignedInt(zcu));
- const rhs_is_signed = if (try sema.resolveDefinedValue(block, rhs_src, rhs)) |rhs_val|
+ const rhs_is_signed = if (maybe_rhs_val) |rhs_val|
!(try rhs_val.compareAllWithZeroSema(.gte, pt))
else
(rhs_ty.isRuntimeFloat() or rhs_ty.isSignedInt(zcu));
@@ -33908,19 +33923,8 @@ fn cmpNumeric(
var dest_float_type: ?Type = null;
var lhs_bits: usize = undefined;
- if (try sema.resolveValueResolveLazy(lhs)) |lhs_val| {
- if (lhs_val.isUndef(zcu))
- return pt.undefRef(Type.bool);
- if (lhs_val.isNan(zcu)) switch (op) {
- .neq => return .bool_true,
- else => return .bool_false,
- };
- if (lhs_val.isInf(zcu)) switch (op) {
- .neq => return .bool_true,
- .eq => return .bool_false,
- .gt, .gte => return if (lhs_val.isNegativeInf(zcu)) .bool_false else .bool_true,
- .lt, .lte => return if (lhs_val.isNegativeInf(zcu)) .bool_true else .bool_false,
- };
+ if (maybe_lhs_val) |unresolved_lhs_val| {
+ const lhs_val = try sema.resolveLazyValue(unresolved_lhs_val);
if (!rhs_is_signed) {
switch (lhs_val.orderAgainstZero(zcu)) {
.gt => {},
@@ -33966,19 +33970,8 @@ fn cmpNumeric(
}
var rhs_bits: usize = undefined;
- if (try sema.resolveValueResolveLazy(rhs)) |rhs_val| {
- if (rhs_val.isUndef(zcu))
- return pt.undefRef(Type.bool);
- if (rhs_val.isNan(zcu)) switch (op) {
- .neq => return .bool_true,
- else => return .bool_false,
- };
- if (rhs_val.isInf(zcu)) switch (op) {
- .neq => return .bool_true,
- .eq => return .bool_false,
- .gt, .gte => return if (rhs_val.isNegativeInf(zcu)) .bool_true else .bool_false,
- .lt, .lte => return if (rhs_val.isNegativeInf(zcu)) .bool_false else .bool_true,
- };
+ if (maybe_rhs_val) |unresolved_rhs_val| {
+ const rhs_val = try sema.resolveLazyValue(unresolved_rhs_val);
if (!lhs_is_signed) {
switch (rhs_val.orderAgainstZero(zcu)) {
.gt => {},
@@ -34045,90 +34038,49 @@ fn compareIntsOnlyPossibleResult(
lhs_val: Value,
op: std.math.CompareOperator,
rhs_ty: Type,
-) Allocator.Error!?bool {
+) SemaError!?bool {
const pt = sema.pt;
const zcu = pt.zcu;
- const rhs_info = rhs_ty.intInfo(zcu);
- const vs_zero = lhs_val.orderAgainstZeroSema(pt) catch unreachable;
- const is_zero = vs_zero == .eq;
- const is_negative = vs_zero == .lt;
- const is_positive = vs_zero == .gt;
- // Anything vs. zero-sized type has guaranteed outcome.
- if (rhs_info.bits == 0) return switch (op) {
- .eq, .lte, .gte => is_zero,
- .neq, .lt, .gt => !is_zero,
- };
+ const min_rhs = try rhs_ty.minInt(pt, rhs_ty);
+ const max_rhs = try rhs_ty.maxInt(pt, rhs_ty);
- // Special case for i1, which can only be 0 or -1.
- // Zero and positive ints have guaranteed outcome.
- if (rhs_info.bits == 1 and rhs_info.signedness == .signed) {
- if (is_positive) return switch (op) {
- .gt, .gte, .neq => true,
- .lt, .lte, .eq => false,
- };
- if (is_zero) return switch (op) {
- .gte => true,
- .lt => false,
- .gt, .lte, .eq, .neq => null,
- };
+ if (min_rhs.toIntern() == max_rhs.toIntern()) {
+ // RHS is effectively comptime-known.
+ return try Value.compareHeteroSema(lhs_val, op, min_rhs, pt);
}
- // Negative vs. unsigned has guaranteed outcome.
- if (rhs_info.signedness == .unsigned and is_negative) return switch (op) {
- .eq, .gt, .gte => false,
- .neq, .lt, .lte => true,
- };
-
- const sign_adj = @intFromBool(!is_negative and rhs_info.signedness == .signed);
- const req_bits = lhs_val.intBitCountTwosComp(zcu) + sign_adj;
-
- // No sized type can have more than 65535 bits.
- // The RHS type operand is either a runtime value or sized (but undefined) constant.
- if (req_bits > 65535) return switch (op) {
- .lt, .lte => is_negative,
- .gt, .gte => is_positive,
- .eq => false,
- .neq => true,
- };
- const fits = req_bits <= rhs_info.bits;
+ const against_min = try lhs_val.orderAdvanced(min_rhs, .sema, zcu, pt.tid);
+ const against_max = try lhs_val.orderAdvanced(max_rhs, .sema, zcu, pt.tid);
- // Oversized int has guaranteed outcome.
switch (op) {
- .eq => return if (!fits) false else null,
- .neq => return if (!fits) true else null,
- .lt, .lte => if (!fits) return is_negative,
- .gt, .gte => if (!fits) return !is_negative,
+ .eq => {
+ if (against_min.compare(.lt)) return false;
+ if (against_max.compare(.gt)) return false;
+ },
+ .neq => {
+ if (against_min.compare(.lt)) return true;
+ if (against_max.compare(.gt)) return true;
+ },
+ .lt => {
+ if (against_min.compare(.lt)) return true;
+ if (against_max.compare(.gte)) return false;
+ },
+ .gt => {
+ if (against_max.compare(.gt)) return true;
+ if (against_min.compare(.lte)) return false;
+ },
+ .lte => {
+ if (against_min.compare(.lte)) return true;
+ if (against_max.compare(.gt)) return false;
+ },
+ .gte => {
+ if (against_max.compare(.gte)) return true;
+ if (against_min.compare(.lt)) return false;
+ },
}
- // For any other comparison, we need to know if the LHS value is
- // equal to the maximum or minimum possible value of the RHS type.
- const is_min, const is_max = edge: {
- if (is_zero and rhs_info.signedness == .unsigned) break :edge .{ true, false };
-
- if (req_bits != rhs_info.bits) break :edge .{ false, false };
-
- const ty = try pt.intType(
- if (is_negative) .signed else .unsigned,
- @intCast(req_bits),
- );
- const pop_count = lhs_val.popCount(ty, zcu);
-
- if (is_negative) {
- break :edge .{ pop_count == 1, false };
- } else {
- break :edge .{ false, pop_count == req_bits - sign_adj };
- }
- };
-
- assert(fits);
- return switch (op) {
- .lt => if (is_max) false else null,
- .lte => if (is_min) true else null,
- .gt => if (is_min) false else null,
- .gte => if (is_max) true else null,
- .eq, .neq => unreachable,
- };
+ return null;
}
/// Asserts that lhs and rhs types are both vectors.
src/Type.zig
@@ -3040,8 +3040,7 @@ pub fn minInt(ty: Type, pt: Zcu.PerThread, dest_ty: Type) !Value {
pub fn minIntScalar(ty: Type, pt: Zcu.PerThread, dest_ty: Type) !Value {
const zcu = pt.zcu;
const info = ty.intInfo(zcu);
- if (info.signedness == .unsigned) return pt.intValue(dest_ty, 0);
- if (info.bits == 0) return pt.intValue(dest_ty, -1);
+ if (info.signedness == .unsigned or info.bits == 0) return pt.intValue(dest_ty, 0);
if (std.math.cast(u6, info.bits - 1)) |shift| {
const n = @as(i64, std.math.minInt(i64)) >> (63 - shift);
@@ -3072,10 +3071,7 @@ pub fn maxIntScalar(ty: Type, pt: Zcu.PerThread, dest_ty: Type) !Value {
const info = ty.intInfo(pt.zcu);
switch (info.bits) {
- 0 => return switch (info.signedness) {
- .signed => try pt.intValue(dest_ty, -1),
- .unsigned => try pt.intValue(dest_ty, 0),
- },
+ 0 => return pt.intValue(dest_ty, 0),
1 => return switch (info.signedness) {
.signed => try pt.intValue(dest_ty, 0),
.unsigned => try pt.intValue(dest_ty, 1),
src/Value.zig
@@ -191,7 +191,7 @@ pub fn toBigIntAdvanced(
comptime strat: ResolveStrat,
zcu: *Zcu,
tid: strat.Tid(),
-) Zcu.CompileError!BigIntConst {
+) Zcu.SemaError!BigIntConst {
const ip = &zcu.intern_pool;
return switch (val.toIntern()) {
.bool_false => BigIntMutable.init(&space.limbs, 0).toConst(),
@@ -1038,7 +1038,7 @@ pub fn orderAgainstZeroInner(
comptime strat: ResolveStrat,
zcu: *Zcu,
tid: strat.Tid(),
-) Zcu.CompileError!std.math.Order {
+) Zcu.SemaError!std.math.Order {
return switch (lhs.toIntern()) {
.bool_false => .eq,
.bool_true => .gt,
test/behavior/math.zig
@@ -1729,3 +1729,65 @@ test "@clz works on both vector and scalar inputs" {
try std.testing.expectEqual(@as(u6, 31), a);
try std.testing.expectEqual([_]u6{ 31, 31, 31, 31 }, b);
}
+
+test "runtime comparison to NaN is comptime-known" {
+ if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
+ if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
+ if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+ if (builtin.cpu.arch.isArmOrThumb() and builtin.target.floatAbi() == .soft) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/21234
+
+ const S = struct {
+ fn doTheTest(comptime F: type, x: F) void {
+ const nan = math.nan(F);
+ if (!(nan != x)) comptime unreachable;
+ if (nan == x) comptime unreachable;
+ if (nan > x) comptime unreachable;
+ if (nan < x) comptime unreachable;
+ if (nan >= x) comptime unreachable;
+ if (nan <= x) comptime unreachable;
+ }
+ };
+
+ S.doTheTest(f16, 123.0);
+ S.doTheTest(f32, 123.0);
+ S.doTheTest(f64, 123.0);
+ S.doTheTest(f128, 123.0);
+ comptime S.doTheTest(f16, 123.0);
+ comptime S.doTheTest(f32, 123.0);
+ comptime S.doTheTest(f64, 123.0);
+ comptime S.doTheTest(f128, 123.0);
+}
+
+test "runtime int comparison to inf is comptime-known" {
+ if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
+ if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
+ if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
+ if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+ if (builtin.cpu.arch.isArmOrThumb() and builtin.target.floatAbi() == .soft) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/21234
+
+ const S = struct {
+ fn doTheTest(comptime F: type, x: u32) void {
+ const inf = math.inf(F);
+ if (!(inf != x)) comptime unreachable;
+ if (inf == x) comptime unreachable;
+ if (x > inf) comptime unreachable;
+ if (x >= inf) comptime unreachable;
+ if (!(x < inf)) comptime unreachable;
+ if (!(x <= inf)) comptime unreachable;
+ }
+ };
+
+ S.doTheTest(f16, 123);
+ S.doTheTest(f32, 123);
+ S.doTheTest(f64, 123);
+ S.doTheTest(f128, 123);
+ comptime S.doTheTest(f16, 123);
+ comptime S.doTheTest(f32, 123);
+ comptime S.doTheTest(f64, 123);
+ comptime S.doTheTest(f128, 123);
+}