authorgravatar for git@vexu.euVeikka Tuominen <git@vexu.eu> 2020-07-22 16:27:27+03:00
committergravatar for git@vexu.euVeikka Tuominen <git@vexu.eu> 2020-07-29 18:03:44+03:00
log1f8f434b9c672837d307b50d0fb3c87b8a0ec16a
treecfc1e161ce8e4d97c3f0bb23790a38999b4c4798
parent547e520359b983d301670b8a3b37df67d4ab1a53
signature Commit is signed but in an unrecognized format.

compiler_rt: add floatditf

4 files changed, 66 insertions(+), 2 deletions(-)

lib/std/special/compiler_rt.zig+1
...@@ -92,6 +92,7 @@ comptime {...@@ -92,6 +92,7 @@ comptime {
92 @export(@import("compiler_rt/floatunsidf.zig").__floatunsidf, .{ .name = "__floatunsidf", .linkage = linkage });92 @export(@import("compiler_rt/floatunsidf.zig").__floatunsidf, .{ .name = "__floatunsidf", .linkage = linkage });
93 @export(@import("compiler_rt/floatundidf.zig").__floatundidf, .{ .name = "__floatundidf", .linkage = linkage });93 @export(@import("compiler_rt/floatundidf.zig").__floatundidf, .{ .name = "__floatundidf", .linkage = linkage });
9494
95 @export(@import("compiler_rt/floatditf.zig").__floatditf, .{ .name = "__floatditf", .linkage = linkage });
95 @export(@import("compiler_rt/floattitf.zig").__floattitf, .{ .name = "__floattitf", .linkage = linkage });96 @export(@import("compiler_rt/floattitf.zig").__floattitf, .{ .name = "__floattitf", .linkage = linkage });
96 @export(@import("compiler_rt/floattidf.zig").__floattidf, .{ .name = "__floattidf", .linkage = linkage });97 @export(@import("compiler_rt/floattidf.zig").__floattidf, .{ .name = "__floattidf", .linkage = linkage });
97 @export(@import("compiler_rt/floattisf.zig").__floattisf, .{ .name = "__floattisf", .linkage = linkage });98 @export(@import("compiler_rt/floattisf.zig").__floattisf, .{ .name = "__floattisf", .linkage = linkage });
lib/std/special/compiler_rt/floatditf.zig created+38
...@@ -0,0 +1,38 @@
1const builtin = @import("builtin");
2const is_test = builtin.is_test;
3const std = @import("std");
4const maxInt = std.math.maxInt;
5
6const significandBits = 112;
7const exponentBias = 16383;
8const implicitBit = (@as(u128, 1) << significandBits);
9
10pub fn __floatditf(arg: i64) callconv(.C) f128 {
11 @setRuntimeSafety(is_test);
12
13 if (arg == 0)
14 return 0.0;
15
16 // All other cases begin by extracting the sign and absolute value of a
17 var sign: u128 = 0;
18 var aAbs = @bitCast(u64, arg);
19 if (arg < 0) {
20 sign = 1 << 127;
21 aAbs = ~@bitCast(u64, arg)+ 1;
22 }
23
24 // Exponent of (fp_t)a is the width of abs(a).
25 const exponent = 63 - @clz(u64, aAbs);
26 var result: u128 = undefined;
27
28 // Shift a into the significand field, rounding if it is a right-shift
29 const shift = significandBits - exponent;
30 result = @as(u128, aAbs) << shift ^ implicitBit;
31
32 result += (@as(u128, exponent) + exponentBias) << significandBits;
33 return @bitCast(f128, result | sign);
34}
35
36test "import floatditf" {
37 _ = @import("floatditf_test.zig");
38}
lib/std/special/compiler_rt/floatditf_test.zig created+26
...@@ -0,0 +1,26 @@
1const __floatditf = @import("floatditf.zig").__floatditf;
2const testing = @import("std").testing;
3
4fn test__floatditf(a: i64, expected: f128) void {
5 const x = __floatditf(a);
6 testing.expect(x == expected);
7}
8
9test "floatditf" {
10 test__floatditf(0x7fffffffffffffff, make_ti(0x403dffffffffffff, 0xfffc000000000000));
11 test__floatditf(0x123456789abcdef1, make_ti(0x403b23456789abcd, 0xef10000000000000));
12 test__floatditf(0x2, make_ti(0x4000000000000000, 0x0));
13 test__floatditf(0x1, make_ti(0x3fff000000000000, 0x0));
14 test__floatditf(0x0, make_ti(0x0, 0x0));
15 test__floatditf(@bitCast(i64, @as(u64, 0xffffffffffffffff)), make_ti(0xbfff000000000000, 0x0));
16 test__floatditf(@bitCast(i64, @as(u64, 0xfffffffffffffffe)), make_ti(0xc000000000000000, 0x0));
17 test__floatditf(-0x123456789abcdef1, make_ti(0xc03b23456789abcd, 0xef10000000000000));
18 test__floatditf(@bitCast(i64, @as(u64, 0x8000000000000000)), make_ti(0xc03e000000000000, 0x0));
19}
20
21fn make_ti(high: u64, low: u64) f128 {
22 var result: u128 = high;
23 result <<= 64;
24 result |= low;
25 return @bitCast(f128, result);
26}
src-self-hosted/value.zig+1-2
...@@ -586,8 +586,7 @@ pub const Value = extern union {...@@ -586,8 +586,7 @@ pub const Value = extern union {
586586
587 .zero => 0,587 .zero => 0,
588 .int_u64 => @intToFloat(T, self.cast(Payload.Int_u64).?.int),588 .int_u64 => @intToFloat(T, self.cast(Payload.Int_u64).?.int),
589 // .int_i64 => @intToFloat(f128, self.cast(Payload.Int_i64).?.int),589 .int_i64 => @intToFloat(T, self.cast(Payload.Int_i64).?.int),
590 .int_i64 => @panic("TODO lld: error: undefined symbol: __floatditf"),
591590
592 .int_big_positive, .int_big_negative => @panic("big int to f128"),591 .int_big_positive, .int_big_negative => @panic("big int to f128"),
593 else => unreachable,592 else => unreachable,