glsl: Add "built-in" functions to do 64%64 => 64 modulus

These functions are directly available in shaders.  A #define is added
to detect the presence.  This allows these functions to be tested using
piglit regardless of whether the driver uses them for lowering.  The
GLSL spec says that functions and macros beginning with __ are reserved
for use by the implementation... hey, that's us!

v2: Use function inlining.

Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Matt Turner <[email protected]>

1 files changed, 18 insertions, 0 deletions

diff --git a/src/compiler/glsl/int64.glsl b/src/compiler/glsl/int64.glsl
index 84e80ee349b..b1036e379c9 100644
--- a/src/compiler/glsl/int64.glsl
+++ b/src/compiler/glsl/int64.glsl
@@ -101,3 +101,21 @@ idiv64(ivec2 _n, ivec2 _d)
 
    return negate ? unpackInt2x32(-int64_t(packUint2x32(quot))) : ivec2(quot);
 }
+
+uvec2
+umod64(uvec2 n, uvec2 d)
+{
+   return udivmod64(n, d).zw;
+}
+
+ivec2
+imod64(ivec2 _n, ivec2 _d)
+{
+   const bool negate = (_n.y < 0) != (_d.y < 0);
+   uvec2 n = unpackUint2x32(uint64_t(abs(packInt2x32(_n))));
+   uvec2 d = unpackUint2x32(uint64_t(abs(packInt2x32(_d))));
+
+   uvec2 rem = udivmod64(n, d).zy;
+
+   return negate ? unpackInt2x32(-int64_t(packUint2x32(rem))) : ivec2(rem);
+}