Commit 379950f81d
Changed files (2)
std
special
compiler_rt
std/special/compiler_rt/truncXfYf2.zig
@@ -4,7 +4,13 @@ pub extern fn __truncsfhf2(a: f32) u16 {
return @bitCast(u16, truncXfYf2(f16, f32, a));
}
-const CHAR_BIT = 8;
+pub extern fn __trunctfsf2(a: f128) f32 {
+ return truncXfYf2(f32, f128, a);
+}
+
+pub extern fn __trunctfdf2(a: f128) f64 {
+ return truncXfYf2(f64, f128, a);
+}
inline fn truncXfYf2(comptime dst_t: type, comptime src_t: type, a: src_t) dst_t {
const src_rep_t = @IntType(false, @typeInfo(src_t).Float.bits);
@@ -16,7 +22,7 @@ inline fn truncXfYf2(comptime dst_t: type, comptime src_t: type, a: src_t) dst_t
// Various constants whose values follow from the type parameters.
// Any reasonable optimizer will fold and propagate all of these.
- const srcBits = @sizeOf(src_t) * CHAR_BIT;
+ const srcBits = src_t.bit_count;
const srcExpBits = srcBits - srcSigBits - 1;
const srcInfExp = (1 << srcExpBits) - 1;
const srcExpBias = srcInfExp >> 1;
@@ -31,7 +37,7 @@ inline fn truncXfYf2(comptime dst_t: type, comptime src_t: type, a: src_t) dst_t
const srcQNaN = 1 << (srcSigBits - 1);
const srcNaNCode = srcQNaN - 1;
- const dstBits = @sizeOf(dst_t) * CHAR_BIT;
+ const dstBits = dst_t.bit_count;
const dstExpBits = dstBits - dstSigBits - 1;
const dstInfExp = (1 << dstExpBits) - 1;
const dstExpBias = dstInfExp >> 1;
@@ -79,8 +85,8 @@ inline fn truncXfYf2(comptime dst_t: type, comptime src_t: type, a: src_t) dst_t
// a underflows on conversion to the destination type or is an exact
// zero. The result may be a denormal or zero. Extract the exponent
// to get the shift amount for the denormalization.
- const aExp: u32 = aAbs >> srcSigBits;
- const shift: u32 = srcExpBias - dstExpBias - aExp + 1;
+ const aExp = aAbs >> srcSigBits;
+ const shift = srcExpBias - dstExpBias - aExp + 1;
const significand: src_rep_t = (aRep & srcSignificandMask) | srcMinNormal;
std/special/compiler_rt/truncXfYf2_test.zig
@@ -11,54 +11,124 @@ fn test__truncsfhf2(a: u32, expected: u16) void {
}
test "truncsfhf2" {
- test__truncsfhf2(0x7fc00000, 0x7e00); // qNaN
- test__truncsfhf2(0x7fe00000, 0x7f00); // sNaN
+ test__truncsfhf2(0x7fc00000, 0x7e00); // qNaN
+ test__truncsfhf2(0x7fe00000, 0x7f00); // sNaN
- test__truncsfhf2(0, 0); // 0
- test__truncsfhf2(0x80000000, 0x8000); // -0
+ test__truncsfhf2(0, 0); // 0
+ test__truncsfhf2(0x80000000, 0x8000); // -0
- test__truncsfhf2(0x7f800000, 0x7c00); // inf
- test__truncsfhf2(0xff800000, 0xfc00); // -inf
+ test__truncsfhf2(0x7f800000, 0x7c00); // inf
+ test__truncsfhf2(0xff800000, 0xfc00); // -inf
- test__truncsfhf2(0x477ff000, 0x7c00); // 65520 -> inf
- test__truncsfhf2(0xc77ff000, 0xfc00); // -65520 -> -inf
+ test__truncsfhf2(0x477ff000, 0x7c00); // 65520 -> inf
+ test__truncsfhf2(0xc77ff000, 0xfc00); // -65520 -> -inf
- test__truncsfhf2(0x71cc3892, 0x7c00); // 0x1.987124876876324p+100 -> inf
- test__truncsfhf2(0xf1cc3892, 0xfc00); // -0x1.987124876876324p+100 -> -inf
+ test__truncsfhf2(0x71cc3892, 0x7c00); // 0x1.987124876876324p+100 -> inf
+ test__truncsfhf2(0xf1cc3892, 0xfc00); // -0x1.987124876876324p+100 -> -inf
- test__truncsfhf2(0x38800000, 0x0400); // normal (min), 2**-14
- test__truncsfhf2(0xb8800000, 0x8400); // normal (min), -2**-14
+ test__truncsfhf2(0x38800000, 0x0400); // normal (min), 2**-14
+ test__truncsfhf2(0xb8800000, 0x8400); // normal (min), -2**-14
- test__truncsfhf2(0x477fe000, 0x7bff); // normal (max), 65504
- test__truncsfhf2(0xc77fe000, 0xfbff); // normal (max), -65504
+ test__truncsfhf2(0x477fe000, 0x7bff); // normal (max), 65504
+ test__truncsfhf2(0xc77fe000, 0xfbff); // normal (max), -65504
- test__truncsfhf2(0x477fe100, 0x7bff); // normal, 65505 -> 65504
- test__truncsfhf2(0xc77fe100, 0xfbff); // normal, -65505 -> -65504
+ test__truncsfhf2(0x477fe100, 0x7bff); // normal, 65505 -> 65504
+ test__truncsfhf2(0xc77fe100, 0xfbff); // normal, -65505 -> -65504
- test__truncsfhf2(0x477fef00, 0x7bff); // normal, 65519 -> 65504
- test__truncsfhf2(0xc77fef00, 0xfbff); // normal, -65519 -> -65504
+ test__truncsfhf2(0x477fef00, 0x7bff); // normal, 65519 -> 65504
+ test__truncsfhf2(0xc77fef00, 0xfbff); // normal, -65519 -> -65504
- test__truncsfhf2(0x3f802000, 0x3c01); // normal, 1 + 2**-10
- test__truncsfhf2(0xbf802000, 0xbc01); // normal, -1 - 2**-10
+ test__truncsfhf2(0x3f802000, 0x3c01); // normal, 1 + 2**-10
+ test__truncsfhf2(0xbf802000, 0xbc01); // normal, -1 - 2**-10
- test__truncsfhf2(0x3eaaa000, 0x3555); // normal, approx. 1/3
- test__truncsfhf2(0xbeaaa000, 0xb555); // normal, approx. -1/3
+ test__truncsfhf2(0x3eaaa000, 0x3555); // normal, approx. 1/3
+ test__truncsfhf2(0xbeaaa000, 0xb555); // normal, approx. -1/3
- test__truncsfhf2(0x40490fdb, 0x4248); // normal, 3.1415926535
- test__truncsfhf2(0xc0490fdb, 0xc248); // normal, -3.1415926535
+ test__truncsfhf2(0x40490fdb, 0x4248); // normal, 3.1415926535
+ test__truncsfhf2(0xc0490fdb, 0xc248); // normal, -3.1415926535
- test__truncsfhf2(0x45cc3892, 0x6e62); // normal, 0x1.987124876876324p+12
+ test__truncsfhf2(0x45cc3892, 0x6e62); // normal, 0x1.987124876876324p+12
- test__truncsfhf2(0x3f800000, 0x3c00); // normal, 1
- test__truncsfhf2(0x38800000, 0x0400); // normal, 0x1.0p-14
+ test__truncsfhf2(0x3f800000, 0x3c00); // normal, 1
+ test__truncsfhf2(0x38800000, 0x0400); // normal, 0x1.0p-14
- test__truncsfhf2(0x33800000, 0x0001); // denormal (min), 2**-24
- test__truncsfhf2(0xb3800000, 0x8001); // denormal (min), -2**-24
+ test__truncsfhf2(0x33800000, 0x0001); // denormal (min), 2**-24
+ test__truncsfhf2(0xb3800000, 0x8001); // denormal (min), -2**-24
- test__truncsfhf2(0x387fc000, 0x03ff); // denormal (max), 2**-14 - 2**-24
- test__truncsfhf2(0xb87fc000, 0x83ff); // denormal (max), -2**-14 + 2**-24
+ test__truncsfhf2(0x387fc000, 0x03ff); // denormal (max), 2**-14 - 2**-24
+ test__truncsfhf2(0xb87fc000, 0x83ff); // denormal (max), -2**-14 + 2**-24
- test__truncsfhf2(0x35800000, 0x0010); // denormal, 0x1.0p-20
- test__truncsfhf2(0x33280000, 0x0001); // denormal, 0x1.5p-25 -> 0x1.0p-24
- test__truncsfhf2(0x33000000, 0x0000); // 0x1.0p-25 -> zero
+ test__truncsfhf2(0x35800000, 0x0010); // denormal, 0x1.0p-20
+ test__truncsfhf2(0x33280000, 0x0001); // denormal, 0x1.5p-25 -> 0x1.0p-24
+ test__truncsfhf2(0x33000000, 0x0000); // 0x1.0p-25 -> zero
+}
+
+const __trunctfsf2 = @import("truncXfYf2.zig").__trunctfsf2;
+
+fn test__trunctfsf2(a: f128, expected: u32) void {
+ const x = __trunctfsf2(a);
+
+ const rep = @bitCast(u32, x);
+ if (rep == expected) {
+ return;
+ }
+ // test other possible NaN representation(signal NaN)
+ else if (expected == 0x7fc00000) {
+ if ((rep & 0x7f800000) == 0x7f800000 and (rep & 0x7fffff) > 0) {
+ return;
+ }
+ }
+
+ @panic("__trunctfsf2 test failure");
+}
+
+test "trunctfsf2" {
+ // qnan
+ test__trunctfsf2(@bitCast(f128, u128(0x7fff800000000000 << 64)), 0x7fc00000);
+ // nan
+ test__trunctfsf2(@bitCast(f128, u128((0x7fff000000000000 | (0x810000000000 & 0xffffffffffff)) << 64)), 0x7fc08000);
+ // inf
+ test__trunctfsf2(@bitCast(f128, u128(0x7fff000000000000 << 64)), 0x7f800000);
+ // zero
+ test__trunctfsf2(0.0, 0x0);
+
+ test__trunctfsf2(0x1.23a2abb4a2ddee355f36789abcdep+5, 0x4211d156);
+ test__trunctfsf2(0x1.e3d3c45bd3abfd98b76a54cc321fp-9, 0x3b71e9e2);
+ test__trunctfsf2(0x1.234eebb5faa678f4488693abcdefp+4534, 0x7f800000);
+ test__trunctfsf2(0x1.edcba9bb8c76a5a43dd21f334634p-435, 0x0);
+}
+
+const __trunctfdf2 = @import("truncXfYf2.zig").__trunctfdf2;
+
+fn test__trunctfdf2(a: f128, expected: u64) void {
+ const x = __trunctfdf2(a);
+
+ const rep = @bitCast(u64, x);
+ if (rep == expected) {
+ return;
+ }
+ // test other possible NaN representation(signal NaN)
+ else if (expected == 0x7ff8000000000000) {
+ if ((rep & 0x7ff0000000000000) == 0x7ff0000000000000 and (rep & 0xfffffffffffff) > 0) {
+ return;
+ }
+ }
+
+ @panic("__trunctfsf2 test failure");
+}
+
+test "trunctfdf2" {
+ // qnan
+ test__trunctfdf2(@bitCast(f128, u128(0x7fff800000000000 << 64)), 0x7ff8000000000000);
+ // nan
+ test__trunctfdf2(@bitCast(f128, u128((0x7fff000000000000 | (0x810000000000 & 0xffffffffffff)) << 64)), 0x7ff8100000000000);
+ // inf
+ test__trunctfdf2(@bitCast(f128, u128(0x7fff000000000000 << 64)), 0x7ff0000000000000);
+ // zero
+ test__trunctfdf2(0.0, 0x0);
+
+ test__trunctfdf2(0x1.af23456789bbaaab347645365cdep+5, 0x404af23456789bbb);
+ test__trunctfdf2(0x1.dedafcff354b6ae9758763545432p-9, 0x3f6dedafcff354b7);
+ test__trunctfdf2(0x1.2f34dd5f437e849b4baab754cdefp+4534, 0x7ff0000000000000);
+ test__trunctfdf2(0x1.edcbff8ad76ab5bf46463233214fp-435, 0x24cedcbff8ad76ab);
}