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std.PackedInt: remove workaround for stage1 bug

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Closes #7635
This commit is contained in:
Veikka Tuominen 2024-03-28 14:03:45 +02:00
parent 2cdc48a632
commit 0588595128
1 changed files with 53 additions and 43 deletions
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84
lib/std/packed_int_array.zig
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@ -66,32 +66,31 @@ pub fn PackedIntIo(comptime Int: type, comptime endian: Endian) type {
fn getBits(bytes: []const u8, comptime Container: type, bit_index: usize) Int {
const container_bits = @bitSizeOf(Container);
const Shift = std.math.Log2Int(Container);
const start_byte = bit_index / 8;
const head_keep_bits = bit_index - (start_byte * 8);
const tail_keep_bits = container_bits - (int_bits + head_keep_bits);
//read bytes as container
const value_ptr = @as(*align(1) const Container, @ptrCast(&bytes[start_byte]));
const value_ptr: *align(1) const Container = @ptrCast(&bytes[start_byte]);
var value = value_ptr.*;
if (endian != native_endian) value = @byteSwap(value);
switch (endian) {
.big => {
value <<= @as(Shift, @intCast(head_keep_bits));
value >>= @as(Shift, @intCast(head_keep_bits));
value >>= @as(Shift, @intCast(tail_keep_bits));
value <<= @intCast(head_keep_bits);
value >>= @intCast(head_keep_bits);
value >>= @intCast(tail_keep_bits);
},
.little => {
value <<= @as(Shift, @intCast(tail_keep_bits));
value >>= @as(Shift, @intCast(tail_keep_bits));
value >>= @as(Shift, @intCast(head_keep_bits));
value <<= @intCast(tail_keep_bits);
value >>= @intCast(tail_keep_bits);
value >>= @intCast(head_keep_bits);
},
}
return @as(Int, @bitCast(@as(UnInt, @truncate(value))));
return @bitCast(@as(UnInt, @truncate(value)));
}
/// Sets the integer at `index` to `val` within the packed data beginning
@ -114,16 +113,16 @@ pub fn PackedIntIo(comptime Int: type, comptime endian: Endian) type {
const start_byte = bit_index / 8;
const head_keep_bits = bit_index - (start_byte * 8);
const tail_keep_bits = container_bits - (int_bits + head_keep_bits);
const keep_shift = switch (endian) {
.big => @as(Shift, @intCast(tail_keep_bits)),
.little => @as(Shift, @intCast(head_keep_bits)),
const keep_shift: Shift = switch (endian) {
.big => @intCast(tail_keep_bits),
.little => @intCast(head_keep_bits),
};
//position the bits where they need to be in the container
const value = @as(Container, @intCast(@as(UnInt, @bitCast(int)))) << keep_shift;
//read existing bytes
const target_ptr = @as(*align(1) Container, @ptrCast(&bytes[start_byte]));
const target_ptr: *align(1) Container = @ptrCast(&bytes[start_byte]);
var target = target_ptr.*;
if (endian != native_endian) target = @byteSwap(target);
@ -156,7 +155,7 @@ pub fn PackedIntIo(comptime Int: type, comptime endian: Endian) type {
if (length == 0) return PackedIntSliceEndian(Int, endian).init(new_bytes[0..0], 0);
var new_slice = PackedIntSliceEndian(Int, endian).init(new_bytes, length);
new_slice.bit_offset = @as(u3, @intCast((bit_index - (start_byte * 8))));
new_slice.bit_offset = @intCast((bit_index - (start_byte * 8)));
return new_slice;
}
@ -214,15 +213,14 @@ pub fn PackedIntArrayEndian(comptime Int: type, comptime endian: Endian, comptim
/// Initialize a packed array using an unpacked array
/// or, more likely, an array literal.
pub fn init(ints: [int_count]Int) Self {
var self = @as(Self, undefined);
var self: Self = undefined;
for (ints, 0..) |int, i| self.set(i, int);
return self;
}
/// Initialize all entries of a packed array to the same value.
pub fn initAllTo(int: Int) Self {
// TODO: use `var self = @as(Self, undefined);` https://github.com/ziglang/zig/issues/7635
var self = Self{ .bytes = [_]u8{0} ** total_bytes, .len = int_count };
var self: Self = undefined;
self.setAll(int);
return self;
}
@ -365,11 +363,11 @@ test "PackedIntArray" {
const expected_bytes = ((bits * int_count) + 7) / 8;
try testing.expect(@sizeOf(PackedArray) == expected_bytes);
var data = @as(PackedArray, undefined);
var data: PackedArray = undefined;
//write values, counting up
var i = @as(usize, 0);
var count = @as(I, 0);
var i: usize = 0;
var count: I = 0;
while (i < data.len) : (i += 1) {
data.set(i, count);
if (bits > 0) count +%= 1;
@ -395,17 +393,29 @@ test "PackedIntIo" {
}
test "PackedIntArray init" {
const S = struct {
fn doTheTest() !void {
const PackedArray = PackedIntArray(u3, 8);
var packed_array = PackedArray.init([_]u3{ 0, 1, 2, 3, 4, 5, 6, 7 });
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array.len) : (i += 1) try testing.expectEqual(@as(u3, @intCast(i)), packed_array.get(i));
}
};
try S.doTheTest();
try comptime S.doTheTest();
}
test "PackedIntArray initAllTo" {
const S = struct {
fn doTheTest() !void {
const PackedArray = PackedIntArray(u3, 8);
var packed_array = PackedArray.initAllTo(5);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array.len) : (i += 1) try testing.expectEqual(@as(u3, 5), packed_array.get(i));
}
};
try S.doTheTest();
try comptime S.doTheTest();
}
test "PackedIntSlice" {
@ -433,8 +443,8 @@ test "PackedIntSlice" {
var data = P.init(&buffer, int_count);
//write values, counting up
var i = @as(usize, 0);
var count = @as(I, 0);
var i: usize = 0;
var count: I = 0;
while (i < data.len) : (i += 1) {
data.set(i, count);
if (bits > 0) count +%= 1;
@ -463,13 +473,13 @@ test "PackedIntSlice of PackedInt(Array/Slice)" {
const Int = std.meta.Int(.unsigned, bits);
const PackedArray = PackedIntArray(Int, int_count);
var packed_array = @as(PackedArray, undefined);
var packed_array: PackedArray = undefined;
const limit = (1 << bits);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array.len) : (i += 1) {
packed_array.set(i, @as(Int, @intCast(i % limit)));
packed_array.set(i, @intCast(i % limit));
}
//slice of array
@ -524,20 +534,20 @@ test "PackedIntSlice accumulating bit offsets" {
// anything
{
const PackedArray = PackedIntArray(u3, 16);
var packed_array = @as(PackedArray, undefined);
var packed_array: PackedArray = undefined;
var packed_slice = packed_array.slice(0, packed_array.len);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array.len - 1) : (i += 1) {
packed_slice = packed_slice.slice(1, packed_slice.len);
}
}
{
const PackedArray = PackedIntArray(u11, 88);
var packed_array = @as(PackedArray, undefined);
var packed_array: PackedArray = undefined;
var packed_slice = packed_array.slice(0, packed_array.len);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array.len - 1) : (i += 1) {
packed_slice = packed_slice.slice(1, packed_slice.len);
}
@ -552,7 +562,7 @@ test "PackedInt(Array/Slice) sliceCast" {
var packed_slice_cast_9 = packed_array.slice(0, (packed_array.len / 9) * 9).sliceCast(u9);
const packed_slice_cast_3 = packed_slice_cast_9.sliceCast(u3);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_slice_cast_2.len) : (i += 1) {
const val = switch (native_endian) {
.big => 0b01,
@ -576,9 +586,9 @@ test "PackedInt(Array/Slice) sliceCast" {
}
i = 0;
while (i < packed_slice_cast_3.len) : (i += 1) {
const val = switch (native_endian) {
.big => if (i % 2 == 0) @as(u3, 0b111) else @as(u3, 0b000),
.little => if (i % 2 == 0) @as(u3, 0b111) else @as(u3, 0b000),
const val: u3 = switch (native_endian) {
.big => if (i % 2 == 0) 0b111 else 0b000,
.little => if (i % 2 == 0) 0b111 else 0b000,
};
try testing.expect(packed_slice_cast_3.get(i) == val);
}
@ -591,7 +601,7 @@ test "PackedInt(Array/Slice)Endian" {
try testing.expect(packed_array_be.bytes[0] == 0b00000001);
try testing.expect(packed_array_be.bytes[1] == 0b00100011);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array_be.len) : (i += 1) {
try testing.expect(packed_array_be.get(i) == i);
}
@ -620,7 +630,7 @@ test "PackedInt(Array/Slice)Endian" {
try testing.expect(packed_array_be.bytes[3] == 0b00000001);
try testing.expect(packed_array_be.bytes[4] == 0b00000000);
var i = @as(usize, 0);
var i: usize = 0;
while (i < packed_array_be.len) : (i += 1) {
try testing.expect(packed_array_be.get(i) == i);
}