gallium: use new util_fast_exp2(), _log2(), pow() functions

New code surrounded with #if FAST_MATH to allow comparing against original
code if we need to debug.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
index 88a34a69613..e28b56c842f 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
@@ -57,6 +57,9 @@
 #include "tgsi/tgsi_parse.h"
 #include "tgsi/tgsi_util.h"
 #include "tgsi_exec.h"
+#include "util/u_math.h"
+
+#define FAST_MATH 1
 
 #define TILE_TOP_LEFT     0
 #define TILE_TOP_RIGHT    1
@@ -145,6 +148,8 @@ tgsi_exec_machine_bind_shader(
    tgsi_dump(tokens, 0);
 #endif
 
+   util_init_math();
+
    mach->Tokens = tokens;
    mach->Samplers = samplers;
 
@@ -448,10 +453,17 @@ micro_exp2(
    union tgsi_exec_channel *dst,
    const union tgsi_exec_channel *src)
 {
+#if FAST_MATH
+   dst->f[0] = util_fast_exp2( src->f[0] );
+   dst->f[1] = util_fast_exp2( src->f[1] );
+   dst->f[2] = util_fast_exp2( src->f[2] );
+   dst->f[3] = util_fast_exp2( src->f[3] );
+#else
    dst->f[0] = powf( 2.0f, src->f[0] );
    dst->f[1] = powf( 2.0f, src->f[1] );
    dst->f[2] = powf( 2.0f, src->f[2] );
    dst->f[3] = powf( 2.0f, src->f[3] );
+#endif
 }
 
 static void
@@ -528,10 +540,17 @@ micro_lg2(
    union tgsi_exec_channel *dst,
    const union tgsi_exec_channel *src )
 {
+#if FAST_MATH
+   dst->f[0] = util_fast_log2( src->f[0] );
+   dst->f[1] = util_fast_log2( src->f[1] );
+   dst->f[2] = util_fast_log2( src->f[2] );
+   dst->f[3] = util_fast_log2( src->f[3] );
+#else
    dst->f[0] = logf( src->f[0] ) * 1.442695f;
    dst->f[1] = logf( src->f[1] ) * 1.442695f;
    dst->f[2] = logf( src->f[2] ) * 1.442695f;
    dst->f[3] = logf( src->f[3] ) * 1.442695f;
+#endif
 }
 
 static void
@@ -796,10 +815,17 @@ micro_pow(
    const union tgsi_exec_channel *src0,
    const union tgsi_exec_channel *src1 )
 {
+#if FAST_MATH
+   dst->f[0] = util_fast_pow( src0->f[0], src1->f[0] );
+   dst->f[1] = util_fast_pow( src0->f[1], src1->f[1] );
+   dst->f[2] = util_fast_pow( src0->f[2], src1->f[2] );
+   dst->f[3] = util_fast_pow( src0->f[3], src1->f[3] );
+#else
    dst->f[0] = powf( src0->f[0], src1->f[0] );
    dst->f[1] = powf( src0->f[1], src1->f[1] );
    dst->f[2] = powf( src0->f[2], src1->f[2] );
    dst->f[3] = powf( src0->f[3], src1->f[3] );
+#endif
 }
 
 static void
@@ -2024,7 +2050,11 @@ exec_instruction(
     /* TGSI_OPCODE_EX2 */
       FETCH(&r[0], 0, CHAN_X);
 
+#if FAST_MATH
+      micro_exp2( &r[0], &r[0] );
+#else
       micro_pow( &r[0], &mach->Temps[TEMP_2_I].xyzw[TEMP_2_C], &r[0] );
+#endif
 
       FOR_EACH_ENABLED_CHANNEL( *inst, chan_index ) {
 	 STORE( &r[0], 0, chan_index );