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[fdlibm] Inline coefficients for __kernel_sin and __kernel_cos.

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Loading the coefficients from a the constants typed array is currently
blocking inlining MathSin and MathCos into TurboFan generated code,
because there is no type feedback and hence TurboFan has to generate a
LOAD_IC for every coefficient.

R=yanggou@chromium.org
BUG=v8:3952
LOG=n

Review URL: https://codereview.chromium.org/989133002

Cr-Commit-Position: refs/heads/master@{#27057}
This commit is contained in:
Benedikt Meurer 2015-03-09 08:29:57 +01:00
parent 3c4a32dcdc
commit 9bce5b347f
1 changed files with 19 additions and 15 deletions
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34
src/third_party/fdlibm/fdlibm.js vendored
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@ -141,16 +141,18 @@ endmacro
// then 3 2
// sin(x) = X + (S1*X + (X *(r-Y/2)+Y))
//
macro KSIN(x)
kMath[7+x]
endmacro
const S1 = -1.66666666666666324348e-01;
const S2 = 8.33333333332248946124e-03;
const S3 = -1.98412698298579493134e-04;
const S4 = 2.75573137070700676789e-06;
const S5 = -2.50507602534068634195e-08;
const S6 = 1.58969099521155010221e-10;
macro RETURN_KERNELSIN(X, Y, SIGN)
var z = X * X;
var v = z * X;
var r = KSIN(1) + z * (KSIN(2) + z * (KSIN(3) +
z * (KSIN(4) + z * KSIN(5))));
return (X - ((z * (0.5 * Y - v * r) - Y) - v * KSIN(0))) SIGN;
var r = S2 + z * (S3 + z * (S4 + z * (S5 + z * S6)));
return (X - ((z * (0.5 * Y - v * r) - Y) - v * S1)) SIGN;
endmacro
// __kernel_cos(X, Y)
@ -185,15 +187,17 @@ endmacro
// magnitude of the latter is at least a quarter of X*X/2,
// thus, reducing the rounding error in the subtraction.
//
macro KCOS(x)
kMath[13+x]
endmacro
const C1 = 4.16666666666666019037e-02;
const C2 = -1.38888888888741095749e-03;
const C3 = 2.48015872894767294178e-05;
const C4 = -2.75573143513906633035e-07;
const C5 = 2.08757232129817482790e-09;
const C6 = -1.13596475577881948265e-11;
macro RETURN_KERNELCOS(X, Y, SIGN)
var ix = %_DoubleHi(X) & 0x7fffffff;
var z = X * X;
var r = z * (KCOS(0) + z * (KCOS(1) + z * (KCOS(2)+
z * (KCOS(3) + z * (KCOS(4) + z * KCOS(5))))));
var r = z * (C1 + z * (C2 + z * (C3 + z * (C4 + z * (C5 + z * C6)))));
if (ix < 0x3fd33333) { // |x| ~< 0.3
return (1 - (0.5 * z - (z * r - X * Y))) SIGN;
} else {
@ -336,22 +340,22 @@ function MathCosSlow(x) {
// ECMA 262 - 15.8.2.16
function MathSin(x) {
x = x * 1; // Convert to number.
x = +x; // Convert to number.
if ((%_DoubleHi(x) & 0x7fffffff) <= 0x3fe921fb) {
// |x| < pi/4, approximately. No reduction needed.
RETURN_KERNELSIN(x, 0, /* empty */);
}
return MathSinSlow(x);
return +MathSinSlow(x);
}
// ECMA 262 - 15.8.2.7
function MathCos(x) {
x = x * 1; // Convert to number.
x = +x; // Convert to number.
if ((%_DoubleHi(x) & 0x7fffffff) <= 0x3fe921fb) {
// |x| < pi/4, approximately. No reduction needed.
RETURN_KERNELCOS(x, 0, /* empty */);
}
return MathCosSlow(x);
return +MathCosSlow(x);
}
// ECMA 262 - 15.8.2.18