ziglang · Jun 30, 2018 · Jun 30, 2018 · Jun 30, 2018 · Jun 30, 2018 · Jun 30, 2018
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -585,7 +585,14 @@ set(ZIG_STD_FILES
     "special/compiler_rt/fixunstfdi.zig"
     "special/compiler_rt/fixunstfsi.zig"
     "special/compiler_rt/fixunstfti.zig"
+    "special/compiler_rt/floatunditf.zig"
+    "special/compiler_rt/floatunsitf.zig"
     "special/compiler_rt/floatuntidf.zig"
+    "special/compiler_rt/floatuntisf.zig"
+    "special/compiler_rt/floatuntitf.zig"
+    "special/compiler_rt/floattidf.zig"
+    "special/compiler_rt/floattisf.zig"
+    "special/compiler_rt/floattitf.zig"
     "special/compiler_rt/muloti4.zig"
     "special/compiler_rt/index.zig"
     "special/compiler_rt/truncXfYf2.zig"

diff --git a/std/fmt/index.zig b/std/fmt/index.zig
@@ -327,7 +327,7 @@ pub fn formatFloatScientific(
     comptime Errors: type,
     output: fn (@typeOf(context), []const u8) Errors!void,
 ) Errors!void {
-    var x = f64(value);
+    var x = @floatCast(f64, value);
 
     // Errol doesn't handle these special cases.
     if (math.signbit(x)) {

diff --git a/std/special/compiler_rt/floattidf.zig b/std/special/compiler_rt/floattidf.zig
@@ -0,0 +1,69 @@
+const builtin = @import("builtin");
+const is_test = builtin.is_test;
+
+const DBL_MANT_DIG = 53;
+
+pub extern fn __floattidf(arg: i128) f64 {
+    @setRuntimeSafety(is_test);
+
+    if (arg == 0)
+        return 0.0;
+
+    var ai = arg;
+    const N: u32 = 128;
+    const si = ai >> @intCast(u7, (N - 1));
+    ai = ((ai ^ si) -% si);
+    var a = @bitCast(u128, ai);
+
+    const sd = @bitCast(i32, N - @clz(a)); // number of significant digits
+    var e: i32 = sd - 1; // exponent
+    if (sd > DBL_MANT_DIG) {
+        //  start:  0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx
+        //  finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR
+        //                                                12345678901234567890123456
+        //  1 = msb 1 bit
+        //  P = bit DBL_MANT_DIG-1 bits to the right of 1
+        //  Q = bit DBL_MANT_DIG bits to the right of 1
+        //  R = "or" of all bits to the right of Q
+        switch (sd) {
+            DBL_MANT_DIG + 1 => {
+                a <<= 1;
+            },
+            DBL_MANT_DIG + 2 => {},
+            else => {
+                const shift1_amt = @intCast(i32, sd - (DBL_MANT_DIG + 2));
+                const shift1_amt_u7 = @intCast(u7, shift1_amt);
+
+                const shift2_amt = @intCast(i32, N + (DBL_MANT_DIG + 2)) - sd;
+                const shift2_amt_u7 = @intCast(u7, shift2_amt);
+
+                a = (a >> shift1_amt_u7) | @boolToInt((a & (@intCast(u128, @maxValue(u128)) >> shift2_amt_u7)) != 0);
+            },
+        }
+        // finish
+        a |= @boolToInt((a & 4) != 0); // Or P into R
+        a += 1; // round - this step may add a significant bit
+        a >>= 2; // dump Q and R
+        // a is now rounded to DBL_MANT_DIG or DBL_MANT_DIG+1 bits
+        if ((a & (u128(1) << DBL_MANT_DIG)) != 0) {
+            a >>= 1;
+            e += 1;
+        }
+        // a is now rounded to DBL_MANT_DIG bits
+    } else {
+        a <<= @intCast(u7, DBL_MANT_DIG - sd);
+        // a is now rounded to DBL_MANT_DIG bits
+    }
+
+    const s = @bitCast(u128, arg) >> (128 - 32);
+    const high: u64 = (@intCast(u64, s) & 0x80000000) | // sign
+        (@intCast(u32, (e + 1023)) << 20) | // exponent
+        (@truncate(u32, a >> 32) & 0x000fffff); // mantissa-high
+    const low: u64 = @truncate(u32, a); // mantissa-low
+
+    return @bitCast(f64, low | (high << 32));
+}
+
+test "import floattidf" {
+    _ = @import("floattidf_test.zig");
+}
diff --git a/std/special/compiler_rt/floattidf_test.zig b/std/special/compiler_rt/floattidf_test.zig
@@ -0,0 +1,84 @@
+const __floattidf = @import("floattidf.zig").__floattidf;
+const assert = @import("std").debug.assert;
+
+fn test__floattidf(a: i128, expected: f64) void {
+    const x = __floattidf(a);
+    assert(x == expected);
+}
+
+test "floattidf" {
+    test__floattidf(0, 0.0);
+
+    test__floattidf(1, 1.0);
+    test__floattidf(2, 2.0);
+    test__floattidf(20, 20.0);
+    test__floattidf(-1, -1.0);
+    test__floattidf(-2, -2.0);
+    test__floattidf(-20, -20.0);
+
+    test__floattidf(0x7FFFFF8000000000, 0x1.FFFFFEp+62);
+    test__floattidf(0x7FFFFFFFFFFFF800, 0x1.FFFFFFFFFFFFEp+62);
+    test__floattidf(0x7FFFFF0000000000, 0x1.FFFFFCp+62);
+    test__floattidf(0x7FFFFFFFFFFFF000, 0x1.FFFFFFFFFFFFCp+62);
+
+    test__floattidf(make_ti(0x8000008000000000, 0), -0x1.FFFFFEp+126);
+    test__floattidf(make_ti(0x8000000000000800, 0), -0x1.FFFFFFFFFFFFEp+126);
+    test__floattidf(make_ti(0x8000010000000000, 0), -0x1.FFFFFCp+126);
+    test__floattidf(make_ti(0x8000000000001000, 0), -0x1.FFFFFFFFFFFFCp+126);
+
+    test__floattidf(make_ti(0x8000000000000000, 0), -0x1.000000p+127);
+    test__floattidf(make_ti(0x8000000000000001, 0), -0x1.000000p+127);
+
+    test__floattidf(0x0007FB72E8000000, 0x1.FEDCBAp+50);
+
+    test__floattidf(0x0007FB72EA000000, 0x1.FEDCBA8p+50);
+    test__floattidf(0x0007FB72EB000000, 0x1.FEDCBACp+50);
+    test__floattidf(0x0007FB72EBFFFFFF, 0x1.FEDCBAFFFFFFCp+50);
+    test__floattidf(0x0007FB72EC000000, 0x1.FEDCBBp+50);
+    test__floattidf(0x0007FB72E8000001, 0x1.FEDCBA0000004p+50);
+
+    test__floattidf(0x0007FB72E6000000, 0x1.FEDCB98p+50);
+    test__floattidf(0x0007FB72E7000000, 0x1.FEDCB9Cp+50);
+    test__floattidf(0x0007FB72E7FFFFFF, 0x1.FEDCB9FFFFFFCp+50);
+    test__floattidf(0x0007FB72E4000001, 0x1.FEDCB90000004p+50);
+    test__floattidf(0x0007FB72E4000000, 0x1.FEDCB9p+50);
+
+    test__floattidf(0x023479FD0E092DC0, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DA1, 0x1.1A3CFE870496Dp+57);
+    test__floattidf(0x023479FD0E092DB0, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DB8, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DB6, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DBF, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DC1, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DC7, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DC8, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DCF, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DD0, 0x1.1A3CFE870496Ep+57);
+    test__floattidf(0x023479FD0E092DD1, 0x1.1A3CFE870496Fp+57);
+    test__floattidf(0x023479FD0E092DD8, 0x1.1A3CFE870496Fp+57);
+    test__floattidf(0x023479FD0E092DDF, 0x1.1A3CFE870496Fp+57);
+    test__floattidf(0x023479FD0E092DE0, 0x1.1A3CFE870496Fp+57);
+
+    test__floattidf(make_ti(0x023479FD0E092DC0, 0), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DA1, 1), 0x1.1A3CFE870496Dp+121);
+    test__floattidf(make_ti(0x023479FD0E092DB0, 2), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DB8, 3), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DB6, 4), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DBF, 5), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DC1, 6), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DC7, 7), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DC8, 8), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DCF, 9), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DD0, 0), 0x1.1A3CFE870496Ep+121);
+    test__floattidf(make_ti(0x023479FD0E092DD1, 11), 0x1.1A3CFE870496Fp+121);
+    test__floattidf(make_ti(0x023479FD0E092DD8, 12), 0x1.1A3CFE870496Fp+121);
+    test__floattidf(make_ti(0x023479FD0E092DDF, 13), 0x1.1A3CFE870496Fp+121);
+    test__floattidf(make_ti(0x023479FD0E092DE0, 14), 0x1.1A3CFE870496Fp+121);
+}
+
+fn make_ti(high: u64, low: u64) i128 {
+    var result: u128 = high;
+    result <<= 64;
+    result |= low;
+    return @bitCast(i128, result);
+}
diff --git a/std/special/compiler_rt/floattisf.zig b/std/special/compiler_rt/floattisf.zig
@@ -0,0 +1,69 @@
+const builtin = @import("builtin");
+const is_test = builtin.is_test;
+
+const FLT_MANT_DIG = 24;
+
+pub extern fn __floattisf(arg: i128) f32 {
+    @setRuntimeSafety(is_test);
+
+    if (arg == 0)
+        return 0.0;
+
+    var ai = arg;
+    const N: u32 = 128;
+    const si = ai >> @intCast(u7, (N - 1));
+    ai = ((ai ^ si) -% si);
+    var a = @bitCast(u128, ai);
+
+    const sd = @bitCast(i32, N - @clz(a)); // number of significant digits
+    var e: i32 = sd - 1; // exponent
+
+    if (sd > FLT_MANT_DIG) {
+        //  start:  0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx
+        //  finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR
+        //                                                12345678901234567890123456
+        //  1 = msb 1 bit
+        //  P = bit FLT_MANT_DIG-1 bits to the right of 1
+        //  Q = bit FLT_MANT_DIG bits to the right of 1
+        //  R = "or" of all bits to the right of Q
+        switch (sd) {
+            FLT_MANT_DIG + 1 => {
+                a <<= 1;
+            },
+            FLT_MANT_DIG + 2 => {},
+            else => {
+                const shift1_amt = @intCast(i32, sd - (FLT_MANT_DIG + 2));
+                const shift1_amt_u7 = @intCast(u7, shift1_amt);
+
+                const shift2_amt = @intCast(i32, N + (FLT_MANT_DIG + 2)) - sd;
+                const shift2_amt_u7 = @intCast(u7, shift2_amt);
+
+                a = (a >> shift1_amt_u7) | @boolToInt((a & (@intCast(u128, @maxValue(u128)) >> shift2_amt_u7)) != 0);
+            },
+        }
+        // finish
+        a |= @boolToInt((a & 4) != 0); // Or P into R
+        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 & (u128(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 is now rounded to FLT_MANT_DIG bits
+    }
+
+    const s = @bitCast(u128, arg) >> (128 - 32);
+    const r = (@intCast(u32, s) & 0x80000000) | // sign
+        (@intCast(u32, (e + 127)) << 23) | // exponent
+        (@truncate(u32, a) & 0x007fffff); // mantissa-high
+
+    return @bitCast(f32, r);
+}
+
+test "import floattisf" {
+    _ = @import("floattisf_test.zig");
+}
diff --git a/std/special/compiler_rt/floattisf_test.zig b/std/special/compiler_rt/floattisf_test.zig
@@ -0,0 +1,60 @@
+const __floattisf = @import("floattisf.zig").__floattisf;
+const assert = @import("std").debug.assert;
+
+fn test__floattisf(a: i128, expected: f32) void {
+    const x = __floattisf(a);
+    assert(x == expected);
+}
+
+test "floattisf" {
+    test__floattisf(0, 0.0);
+
+    test__floattisf(1, 1.0);
+    test__floattisf(2, 2.0);
+    test__floattisf(-1, -1.0);
+    test__floattisf(-2, -2.0);
+
+    test__floattisf(0x7FFFFF8000000000, 0x1.FFFFFEp+62);
+    test__floattisf(0x7FFFFF0000000000, 0x1.FFFFFCp+62);
+
+    test__floattisf(make_ti(0xFFFFFFFFFFFFFFFF, 0x8000008000000000), -0x1.FFFFFEp+62);
+    test__floattisf(make_ti(0xFFFFFFFFFFFFFFFF, 0x8000010000000000), -0x1.FFFFFCp+62);
+
+    test__floattisf(make_ti(0xFFFFFFFFFFFFFFFF, 0x8000000000000000), -0x1.000000p+63);
+    test__floattisf(make_ti(0xFFFFFFFFFFFFFFFF, 0x8000000000000001), -0x1.000000p+63);
+
+    test__floattisf(0x0007FB72E8000000, 0x1.FEDCBAp+50);
+
+    test__floattisf(0x0007FB72EA000000, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72EB000000, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72EBFFFFFF, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72EC000000, 0x1.FEDCBCp+50);
+    test__floattisf(0x0007FB72E8000001, 0x1.FEDCBAp+50);
+
+    test__floattisf(0x0007FB72E6000000, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72E7000000, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72E7FFFFFF, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72E4000001, 0x1.FEDCBAp+50);
+    test__floattisf(0x0007FB72E4000000, 0x1.FEDCB8p+50);
+
+    test__floattisf(make_ti(0x0007FB72E8000000, 0), 0x1.FEDCBAp+114);
+
+    test__floattisf(make_ti(0x0007FB72EA000000, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72EB000000, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72EBFFFFFF, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72EC000000, 0), 0x1.FEDCBCp+114);
+    test__floattisf(make_ti(0x0007FB72E8000001, 0), 0x1.FEDCBAp+114);
+
+    test__floattisf(make_ti(0x0007FB72E6000000, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72E7000000, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72E7FFFFFF, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72E4000001, 0), 0x1.FEDCBAp+114);
+    test__floattisf(make_ti(0x0007FB72E4000000, 0), 0x1.FEDCB8p+114);
+}
+
+fn make_ti(high: u64, low: u64) i128 {
+    var result: u128 = high;
+    result <<= 64;
+    result |= low;
+    return @bitCast(i128, result);
+}
diff --git a/std/special/compiler_rt/floattitf.zig b/std/special/compiler_rt/floattitf.zig
@@ -0,0 +1,69 @@
+const builtin = @import("builtin");
+const is_test = builtin.is_test;
+
+const LDBL_MANT_DIG = 113;
+
+pub extern fn __floattitf(arg: i128) f128 {
+    @setRuntimeSafety(is_test);
+
+    if (arg == 0)
+        return 0.0;
+
+    var ai = arg;
+    const N: u32 = 128;
+    const si = ai >> @intCast(u7, (N - 1));
+    ai = ((ai ^ si) -% si);
+    var a = @bitCast(u128, ai);
+
+    const sd = @bitCast(i32, N - @clz(a)); // number of significant digits
+    var e: i32 = sd - 1; // exponent
+    if (sd > LDBL_MANT_DIG) {
+        //  start:  0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx
+        //  finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR
+        //                                                12345678901234567890123456
+        //  1 = msb 1 bit
+        //  P = bit LDBL_MANT_DIG-1 bits to the right of 1
+        //  Q = bit LDBL_MANT_DIG bits to the right of 1
+        //  R = "or" of all bits to the right of Q
+        switch (sd) {
+            LDBL_MANT_DIG + 1 => {
+                a <<= 1;
+            },
+            LDBL_MANT_DIG + 2 => {},
+            else => {
+                const shift1_amt = @intCast(i32, sd - (LDBL_MANT_DIG + 2));
+                const shift1_amt_u7 = @intCast(u7, shift1_amt);
+
+                const shift2_amt = @intCast(i32, N + (LDBL_MANT_DIG + 2)) - sd;
+                const shift2_amt_u7 = @intCast(u7, shift2_amt);
+
+                a = (a >> shift1_amt_u7) | @boolToInt((a & (@intCast(u128, @maxValue(u128)) >> shift2_amt_u7)) != 0);
+            },
+        }
+        // finish
+        a |= @boolToInt((a & 4) != 0); // Or P into R
+        a += 1; // round - this step may add a significant bit
+        a >>= 2; // dump Q and R
+        // a is now rounded to LDBL_MANT_DIG or LDBL_MANT_DIG+1 bits
+        if ((a & (u128(1) << LDBL_MANT_DIG)) != 0) {
+            a >>= 1;
+            e += 1;
+        }
+        // a is now rounded to LDBL_MANT_DIG bits
+    } else {
+        a <<= @intCast(u7, LDBL_MANT_DIG - sd);
+        // a is now rounded to LDBL_MANT_DIG bits
+    }
+
+    const s = @bitCast(u128, arg) >> (128 - 64);
+    const high: u128 = (@intCast(u64, s) & 0x8000000000000000) | // sign
+        (@intCast(u64, (e + 16383)) << 48) | // exponent
+        (@truncate(u64, a >> 64) & 0x0000ffffffffffff); // mantissa-high
+    const low = @truncate(u64, a); // mantissa-low
+
+    return @bitCast(f128, low | (high << 64));
+}
+
+test "import floattitf" {
+    _ = @import("floattitf_test.zig");
+}