fix exp1m implementation

in the llvm6 branch with assertions on, it failed the test this fixes it
ziglang · Jan 6, 2018 · dde7cc5 · dde7cc5
1 parent 17e68c4
commit dde7cc5
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/std/math/expm1.zig b/std/math/expm1.zig
@@ -4,6 +4,7 @@
 // - expm1(-inf) = -1
 // - expm1(nan)  = nan
 
+const builtin = @import("builtin");
 const std = @import("../index.zig");
 const math = std.math;
 const assert = std.debug.assert;
@@ -18,6 +19,7 @@ pub fn expm1(x: var) -> @typeOf(x) {
 }
 
 fn expm1_32(x_: f32) -> f32 {
+    @setFloatMode(this, builtin.FloatMode.Strict);
     const o_threshold: f32 = 8.8721679688e+01;
     const ln2_hi: f32      = 6.9313812256e-01;
     const ln2_lo: f32      = 9.0580006145e-06;
@@ -122,7 +124,7 @@ fn expm1_32(x_: f32) -> f32 {
         }
     }
 
-    const twopk = @bitCast(f32, u32((0x7F + k) << 23));
+    const twopk = @bitCast(f32, u32((0x7F +% k) << 23));
 
     if (k < 0 or k > 56) {
         var y = x - e + 1.0;
@@ -135,7 +137,7 @@ fn expm1_32(x_: f32) -> f32 {
         return y - 1.0;
     }
 
-    const uf = @bitCast(f32, u32(0x7F - k) << 23);
+    const uf = @bitCast(f32, u32(0x7F -% k) << 23);
     if (k < 23) {
         return (x - e + (1 - uf)) * twopk;
     } else {
@@ -144,6 +146,7 @@ fn expm1_32(x_: f32) -> f32 {
 }
 
 fn expm1_64(x_: f64) -> f64 {
+    @setFloatMode(this, builtin.FloatMode.Strict);
     const o_threshold: f64 = 7.09782712893383973096e+02;
     const ln2_hi: f64      = 6.93147180369123816490e-01;
     const ln2_lo: f64      = 1.90821492927058770002e-10;
@@ -251,7 +254,7 @@ fn expm1_64(x_: f64) -> f64 {
         }
     }
 
-    const twopk = @bitCast(f64, u64(0x3FF + k) << 52);
+    const twopk = @bitCast(f64, u64(0x3FF +% k) << 52);
 
     if (k < 0 or k > 56) {
         var y = x - e + 1.0;
@@ -264,7 +267,7 @@ fn expm1_64(x_: f64) -> f64 {
         return y - 1.0;
     }
 
-    const uf = @bitCast(f64, u64(0x3FF - k) << 52);
+    const uf = @bitCast(f64, u64(0x3FF -% k) << 52);
     if (k < 20) {
         return (x - e + (1 - uf)) * twopk;
     } else {