motiejus/zig
1
Fork 0
Code Releases Activity

Sema: consider type bounds when refining result type of @min/@max

Browse Source 
I achieved this through a major refactor of the logic of analyzeMinMax.
This change should be compatible with vectors of comptime_int, which
Andrew said are supposed to work (but which currently do not).
This commit is contained in:
mlugg
2023-06-14 00:51:31 +01:00
committed by Andrew Kelley
parent 5d9e8f27d0
commit c4cc796695
3 changed files with 239 additions and 112 deletions
Download Patch File Download Diff File Expand all files Collapse all files

85
test/behavior/maximum_minimum.zig
View File

@@ -1,6 +1,7 @@
const std = @import("std");
const builtin = @import("builtin");
const mem = std.mem;
const assert = std.debug.assert;
const expect = std.testing.expect;
const expectEqual = std.testing.expectEqual;
@@ -210,3 +211,87 @@ test "@min/@max on comptime_int" {
try expectEqual(-2, min);
try expectEqual(2, max);
}
test "@min/@max notices bounds from types" {
if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
var x: u16 = 123;
var y: u32 = 456;
var z: u8 = 10;
const min = @min(x, y, z);
const max = @max(x, y, z);
comptime assert(@TypeOf(min) == u8);
comptime assert(@TypeOf(max) == u32);
try expectEqual(z, min);
try expectEqual(y, max);
}
test "@min/@max notices bounds from vector types" {
if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
var x: @Vector(2, u16) = .{ 30, 67 };
var y: @Vector(2, u32) = .{ 20, 500 };
var z: @Vector(2, u8) = .{ 60, 15 };
const min = @min(x, y, z);
const max = @max(x, y, z);
comptime assert(@TypeOf(min) == @Vector(2, u8));
comptime assert(@TypeOf(max) == @Vector(2, u32));
try expectEqual(@Vector(2, u8){ 20, 15 }, min);
try expectEqual(@Vector(2, u32){ 60, 500 }, max);
}
test "@min/@max notices bounds from types when comptime-known value is undef" {
if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
var x: u32 = 1_000_000;
const y: u16 = undefined;
// y is comptime-known, but is undef, so bounds cannot be refined using its value
const min = @min(x, y);
const max = @max(x, y);
comptime assert(@TypeOf(min) == u16);
comptime assert(@TypeOf(max) == u32);
// Cannot assert values as one was undefined
}
test "@min/@max notices bounds from vector types when element of comptime-known vector is undef" {
if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
var x: @Vector(2, u32) = .{ 1_000_000, 12345 };
const y: @Vector(2, u16) = .{ 10, undefined };
// y is comptime-known, but an element is undef, so bounds cannot be refined using its value
const min = @min(x, y);
const max = @max(x, y);
comptime assert(@TypeOf(min) == @Vector(2, u16));
comptime assert(@TypeOf(max) == @Vector(2, u32));
try expectEqual(@as(u16, 10), min[0]);
try expectEqual(@as(u32, 1_000_000), max[0]);
// Cannot assert values at index 1 as one was undefined
}