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authorAndrew Kelley <andrew@ziglang.org>2019-09-26 01:54:45 -0400
committerGitHub <noreply@github.com>2019-09-26 01:54:45 -0400
commit68bb3945708c43109c48bda3664176307d45b62c (patch)
treeafb9731e10cef9d192560b52cd9ae2cf179775c4 /lib/std/special/compiler_rt/floatundidf.zig
parent6128bc728d1e1024a178c16c2149f5b1a167a013 (diff)
parent4637e8f9699af9c3c6cf4df50ef5bb67c7a318a4 (diff)
downloadzig-68bb3945708c43109c48bda3664176307d45b62c.tar.gz
zig-68bb3945708c43109c48bda3664176307d45b62c.zip
Merge pull request #3315 from ziglang/mv-std-lib
Move std/ to lib/std/
Diffstat (limited to 'lib/std/special/compiler_rt/floatundidf.zig')
-rw-r--r--lib/std/special/compiler_rt/floatundidf.zig24
1 files changed, 24 insertions, 0 deletions
diff --git a/lib/std/special/compiler_rt/floatundidf.zig b/lib/std/special/compiler_rt/floatundidf.zig
new file mode 100644
index 0000000000..68759a2acd
--- /dev/null
+++ b/lib/std/special/compiler_rt/floatundidf.zig
@@ -0,0 +1,24 @@
+const builtin = @import("builtin");
+const std = @import("std");
+
+const twop52: f64 = 0x1.0p52;
+const twop84: f64 = 0x1.0p84;
+const twop84_plus_twop52: f64 = 0x1.00000001p84;
+
+pub extern fn __floatundidf(a: u64) f64 {
+ @setRuntimeSafety(builtin.is_test);
+
+ if (a == 0) return 0;
+
+ var high = @bitCast(u64, twop84);
+ var low = @bitCast(u64, twop52);
+
+ high |= a >> 32;
+ low |= a & 0xFFFFFFFF;
+
+ return (@bitCast(f64, high) - twop84_plus_twop52) + @bitCast(f64, low);
+}
+
+test "import floatundidf" {
+ _ = @import("floatundidf_test.zig");
+}