High precision implementation for sin/cos/tan

This implementation allows all dEQP precision test to pass
for sin, cos and tan function tests.

Change-Id: I33a24497dea68ab2de2e65931f50f2dd4298523c
Reviewed-on: https://swiftshader-review.googlesource.com/13555
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>

diff --git a/src/OpenGL/compiler/OutputASM.cpp b/src/OpenGL/compiler/OutputASM.cpp
index 889f44e..f9a4dbb 100644 (file)
--- a/src/OpenGL/compiler/OutputASM.cpp
+++ b/src/OpenGL/compiler/OutputASM.cpp
@@ -1894,6 +1894,12 @@ namespace glsl
                        instruction->dst.integer = (dst->getBasicType() == EbtInt);
                }
 
+               if(src0)
+               {
+                       TIntermTyped* src = src0->getAsTyped();
+                       instruction->dst.partialPrecision = src && (src->getPrecision() <= EbpLow);
+               }
+
                argument(instruction->src[0], src0, index0);
                argument(instruction->src[1], src1, index1);
                argument(instruction->src[2], src2, index2);

diff --git a/src/Shader/ShaderCore.cpp b/src/Shader/ShaderCore.cpp
index 53644b8..017d0f8 100644 (file)
--- a/src/Shader/ShaderCore.cpp
+++ b/src/Shader/ShaderCore.cpp
@@ -287,6 +287,21 @@ namespace sw
                Float4 y = x * Float4(1.59154943e-1f);   // 1/2pi
                y = y - Round(y);
 
+               if(!pp)
+               {
+                       // From the paper: "A Fast, Vectorizable Algorithm for Producing Single-Precision Sine-Cosine Pairs"
+                       // This implementation passes OpenGL ES 3.0 precision requirements, at the cost of more operations:
+                       // !pp : 17 mul, 7 add, 1 sub, 1 reciprocal
+                       //  pp : 4 mul, 2 add, 2 abs
+
+                       Float4 y2 = y * y;
+                       Float4 c1 = y2 * (y2 * (y2 * Float4(-0.0204391631f) + Float4(0.2536086171f)) + Float4(-1.2336977925f)) + Float4(1.0f);
+                       Float4 s1 = y * (y2 * (y2 * (y2 * Float4(-0.0046075748f) + Float4(0.0796819754f)) + Float4(-0.645963615f)) + Float4(1.5707963235f));
+                       Float4 c2 = (c1 * c1) - (s1 * s1);
+                       Float4 s2 = Float4(2.0f) * s1 * c1;
+                       return Float4(2.0f) * s2 * c2 * reciprocal(s2 * s2 + c2 * c2, pp, true);
+               }
+
                const Float4 A = Float4(-16.0f);
                const Float4 B = Float4(8.0f);
                const Float4 C = Float4(7.75160950e-1f);