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compiler-rt: Add missing floatdisf routine

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Add __floatdisf and __aeabi_l2f

Closes #6188
This commit is contained in:
LemonBoy 2020-08-29 14:39:03 +02:00 committed by Andrew Kelley
parent ff4fde767f
commit e355bcce36
4 changed files with 77 additions and 17 deletions
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4
lib/std/special/compiler_rt.zig
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@ -100,7 +100,8 @@ comptime {
@export(@import("compiler_rt/floatditf.zig").__floatditf, .{ .name = "__floatditf", .linkage = linkage });
@export(@import("compiler_rt/floattitf.zig").__floattitf, .{ .name = "__floattitf", .linkage = linkage });
@export(@import("compiler_rt/floattidf.zig").__floattidf, .{ .name = "__floattidf", .linkage = linkage });
@export(@import("compiler_rt/floattisf.zig").__floattisf, .{ .name = "__floattisf", .linkage = linkage });
@export(@import("compiler_rt/floatXisf.zig").__floattisf, .{ .name = "__floattisf", .linkage = linkage });
@export(@import("compiler_rt/floatXisf.zig").__floatdisf, .{ .name = "__floatdisf", .linkage = linkage });
@export(@import("compiler_rt/floatunditf.zig").__floatunditf, .{ .name = "__floatunditf", .linkage = linkage });
@export(@import("compiler_rt/floatunsitf.zig").__floatunsitf, .{ .name = "__floatunsitf", .linkage = linkage });
@ -204,6 +205,7 @@ comptime {
@export(@import("compiler_rt/extendXfYf2.zig").__aeabi_f2d, .{ .name = "__aeabi_f2d", .linkage = linkage });
@export(@import("compiler_rt/floatsiXf.zig").__aeabi_i2d, .{ .name = "__aeabi_i2d", .linkage = linkage });
@export(@import("compiler_rt/floatdidf.zig").__aeabi_l2d, .{ .name = "__aeabi_l2d", .linkage = linkage });
@export(@import("compiler_rt/floatXisf.zig").__aeabi_l2f, .{ .name = "__aeabi_l2f", .linkage = linkage });
@export(@import("compiler_rt/floatunsidf.zig").__aeabi_ui2d, .{ .name = "__aeabi_ui2d", .linkage = linkage });
@export(@import("compiler_rt/floatundidf.zig").__aeabi_ul2d, .{ .name = "__aeabi_ul2d", .linkage = linkage });
@export(@import("compiler_rt/floatunsisf.zig").__aeabi_ui2f, .{ .name = "__aeabi_ui2f", .linkage = linkage });

51
lib/std/special/compiler_rt/floattisf.zig → lib/std/special/compiler_rt/floatXisf.zig
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@ -4,25 +4,28 @@
// The MIT license requires this copyright notice to be included in all copies
// and substantial portions of the software.
const builtin = @import("builtin");
const is_test = builtin.is_test;
const std = @import("std");
const maxInt = std.math.maxInt;
const FLT_MANT_DIG = 24;
pub fn __floattisf(arg: i128) callconv(.C) f32 {
@setRuntimeSafety(is_test);
fn __floatXisf(comptime T: type, arg: T) f32 {
@setRuntimeSafety(builtin.is_test);
if (arg == 0)
return 0.0;
const Z = std.meta.Int(false, T.bit_count);
const S = std.meta.Int(false, T.bit_count - @clz(Z, @as(Z, T.bit_count) - 1));
if (arg == 0) {
return @as(f32, 0.0);
}
var ai = arg;
const N: u32 = 128;
const si = ai >> @intCast(u7, (N - 1));
const N: u32 = T.bit_count;
const si = ai >> @intCast(S, (N - 1));
ai = ((ai ^ si) -% si);
var a = @bitCast(u128, ai);
var a = @bitCast(Z, ai);
const sd = @bitCast(i32, N - @clz(u128, a)); // number of significant digits
const sd = @bitCast(i32, N - @clz(Z, a)); // number of significant digits
var e: i32 = sd - 1; // exponent
if (sd > FLT_MANT_DIG) {
@ -40,12 +43,12 @@ pub fn __floattisf(arg: i128) callconv(.C) f32 {
FLT_MANT_DIG + 2 => {},
else => {
const shift1_amt = @intCast(i32, sd - (FLT_MANT_DIG + 2));
const shift1_amt_u7 = @intCast(u7, shift1_amt);
const shift1_amt_u7 = @intCast(S, shift1_amt);
const shift2_amt = @intCast(i32, N + (FLT_MANT_DIG + 2)) - sd;
const shift2_amt_u7 = @intCast(u7, shift2_amt);
const shift2_amt_u7 = @intCast(S, shift2_amt);
a = (a >> shift1_amt_u7) | @boolToInt((a & (@intCast(u128, maxInt(u128)) >> shift2_amt_u7)) != 0);
a = (a >> shift1_amt_u7) | @boolToInt((a & (@intCast(Z, maxInt(Z)) >> shift2_amt_u7)) != 0);
},
}
// finish
@ -53,17 +56,17 @@ pub fn __floattisf(arg: i128) callconv(.C) f32 {
a += 1; // round - this step may add a significant bit
a >>= 2; // dump Q and R
// a is now rounded to FLT_MANT_DIG or FLT_MANT_DIG+1 bits
if ((a & (@as(u128, 1) << FLT_MANT_DIG)) != 0) {
if ((a & (@as(Z, 1) << FLT_MANT_DIG)) != 0) {
a >>= 1;
e += 1;
}
// a is now rounded to FLT_MANT_DIG bits
} else {
a <<= @intCast(u7, FLT_MANT_DIG - sd);
a <<= @intCast(S, FLT_MANT_DIG - sd);
// a is now rounded to FLT_MANT_DIG bits
}
const s = @bitCast(u128, arg) >> (128 - 32);
const s = @bitCast(Z, arg) >> (T.bit_count - 32);
const r = (@intCast(u32, s) & 0x80000000) | // sign
(@intCast(u32, (e + 127)) << 23) | // exponent
(@truncate(u32, a) & 0x007fffff); // mantissa-high
@ -71,6 +74,24 @@ pub fn __floattisf(arg: i128) callconv(.C) f32 {
return @bitCast(f32, r);
}
pub fn __floatdisf(arg: i64) callconv(.C) f32 {
@setRuntimeSafety(builtin.is_test);
return @call(.{ .modifier = .always_inline }, __floatXisf, .{ i64, arg });
}
pub fn __floattisf(arg: i128) callconv(.C) f32 {
@setRuntimeSafety(builtin.is_test);
return @call(.{ .modifier = .always_inline }, __floatXisf, .{ i128, arg });
}
pub fn __aeabi_l2f(arg: i64) callconv(.AAPCS) f32 {
@setRuntimeSafety(false);
return @call(.{ .modifier = .always_inline }, __floatdisf, .{arg});
}
test "import floattisf" {
_ = @import("floattisf_test.zig");
}
test "import floatdisf" {
_ = @import("floattisf_test.zig");
}

37
lib/std/special/compiler_rt/floatdisf_test.zig Normal file
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@ -0,0 +1,37 @@
// SPDX-License-Identifier: MIT
// Copyright (c) 2015-2020 Zig Contributors
// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
// The MIT license requires this copyright notice to be included in all copies
// and substantial portions of the software.
const __floatdisf = @import("floatXisf.zig").__floatdisf;
const testing = @import("std").testing;
fn test__floatdisf(a: i64, expected: f32) void {
const x = __floatdisf(a);
testing.expect(x == expected);
}
test "floatdisf" {
test__floatdisf(0, 0.0);
test__floatdisf(1, 1.0);
test__floatdisf(2, 2.0);
test__floatdisf(-1, -1.0);
test__floatdisf(-2, -2.0);
test__floatdisf(0x7FFFFF8000000000, 0x1.FFFFFEp+62);
test__floatdisf(0x7FFFFF0000000000, 0x1.FFFFFCp+62);
test__floatdisf(0x8000008000000000, -0x1.FFFFFEp+62);
test__floatdisf(0x8000010000000000, -0x1.FFFFFCp+62);
test__floatdisf(0x8000000000000000, -0x1.000000p+63);
test__floatdisf(0x8000000000000001, -0x1.000000p+63);
test__floatdisf(0x0007FB72E8000000, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72EA000000, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72EB000000, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72EBFFFFFF, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72EC000000, 0x1.FEDCBCp+50);
test__floatdisf(0x0007FB72E8000001, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72E6000000, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72E7000000, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72E7FFFFFF, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72E4000001, 0x1.FEDCBAp+50);
test__floatdisf(0x0007FB72E4000000, 0x1.FEDCB8p+50);
}

2
lib/std/special/compiler_rt/floattisf_test.zig
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@ -3,7 +3,7 @@
// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
// The MIT license requires this copyright notice to be included in all copies
// and substantial portions of the software.
const __floattisf = @import("floattisf.zig").__floattisf;
const __floattisf = @import("floatXisf.zig").__floattisf;
const testing = @import("std").testing;
fn test__floattisf(a: i128, expected: f32) void {