Mesa (master): llvmpipe: Immediate multiplication.
Jose Fonseca
jrfonseca at kemper.freedesktop.org
Sun Oct 25 21:16:58 UTC 2009
Module: Mesa
Branch: master
Commit: e4c5e01c109e51baaad23e90d08e8543b0fd6c07
URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=e4c5e01c109e51baaad23e90d08e8543b0fd6c07
Author: José Fonseca <jfonseca at vmware.com>
Date: Sun Oct 25 11:48:17 2009 +0000
llvmpipe: Immediate multiplication.
---
src/gallium/drivers/llvmpipe/lp_bld_arit.c | 54 ++++++++++++++++++++++
src/gallium/drivers/llvmpipe/lp_bld_arit.h | 5 ++
src/gallium/drivers/llvmpipe/lp_bld_interp.c | 30 +-----------
src/gallium/drivers/llvmpipe/lp_bld_sample_soa.c | 7 +--
4 files changed, 64 insertions(+), 32 deletions(-)
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_arit.c b/src/gallium/drivers/llvmpipe/lp_bld_arit.c
index 93e797c..9c59677 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_arit.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_arit.c
@@ -47,6 +47,7 @@
#include "util/u_memory.h"
#include "util/u_debug.h"
+#include "util/u_math.h"
#include "util/u_string.h"
#include "util/u_cpu_detect.h"
@@ -425,6 +426,59 @@ lp_build_mul(struct lp_build_context *bld,
/**
+ * Small vector x scale multiplication optimization.
+ */
+LLVMValueRef
+lp_build_mul_imm(struct lp_build_context *bld,
+ LLVMValueRef a,
+ int b)
+{
+ LLVMValueRef factor;
+
+ if(b == 0)
+ return bld->zero;
+
+ if(b == 1)
+ return a;
+
+ if(b == -1)
+ return LLVMBuildNeg(bld->builder, a, "");
+
+ if(b == 2 && bld->type.floating)
+ return lp_build_add(bld, a, a);
+
+ if(util_is_pot(b)) {
+ unsigned shift = ffs(b) - 1;
+
+ if(bld->type.floating) {
+#if 0
+ /*
+ * Power of two multiplication by directly manipulating the mantissa.
+ *
+ * XXX: This might not be always faster, it will introduce a small error
+ * for multiplication by zero, and it will produce wrong results
+ * for Inf and NaN.
+ */
+ unsigned mantissa = lp_mantissa(bld->type);
+ factor = lp_build_int_const_scalar(bld->type, (unsigned long long)shift << mantissa);
+ a = LLVMBuildBitCast(bld->builder, a, lp_build_int_vec_type(bld->type), "");
+ a = LLVMBuildAdd(bld->builder, a, factor, "");
+ a = LLVMBuildBitCast(bld->builder, a, lp_build_vec_type(bld->type), "");
+ return a;
+#endif
+ }
+ else {
+ factor = lp_build_const_scalar(bld->type, shift);
+ return LLVMBuildShl(bld->builder, a, factor, "");
+ }
+ }
+
+ factor = lp_build_const_scalar(bld->type, (double)b);
+ return lp_build_mul(bld, a, factor);
+}
+
+
+/**
* Generate a / b
*/
LLVMValueRef
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_arit.h b/src/gallium/drivers/llvmpipe/lp_bld_arit.h
index 4e568c0..62be4b9 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_arit.h
+++ b/src/gallium/drivers/llvmpipe/lp_bld_arit.h
@@ -67,6 +67,11 @@ lp_build_mul(struct lp_build_context *bld,
LLVMValueRef b);
LLVMValueRef
+lp_build_mul_imm(struct lp_build_context *bld,
+ LLVMValueRef a,
+ int b);
+
+LLVMValueRef
lp_build_div(struct lp_build_context *bld,
LLVMValueRef a,
LLVMValueRef b);
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_interp.c b/src/gallium/drivers/llvmpipe/lp_bld_interp.c
index 338dbca..818c0e9 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_interp.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_interp.c
@@ -109,32 +109,6 @@ coeffs_init(struct lp_build_interp_soa_context *bld,
/**
- * Small vector x scale multiplication optimization.
- *
- * TODO: Should be elsewhere.
- */
-static LLVMValueRef
-coeff_multiply(struct lp_build_interp_soa_context *bld,
- LLVMValueRef coeff,
- int step)
-{
- LLVMValueRef factor;
-
- switch(step) {
- case 0:
- return bld->base.zero;
- case 1:
- return coeff;
- case 2:
- return lp_build_add(&bld->base, coeff, coeff);
- default:
- factor = lp_build_const_scalar(bld->base.type, (double)step);
- return lp_build_mul(&bld->base, coeff, factor);
- }
-}
-
-
-/**
* Multiply the dadx and dady with the xstep and ystep respectively.
*/
static void
@@ -149,8 +123,8 @@ coeffs_update(struct lp_build_interp_soa_context *bld)
if (mode != TGSI_INTERPOLATE_CONSTANT) {
for(chan = 0; chan < NUM_CHANNELS; ++chan) {
if(mask & (1 << chan)) {
- bld->dadx[attrib][chan] = coeff_multiply(bld, bld->dadx[attrib][chan], bld->xstep);
- bld->dady[attrib][chan] = coeff_multiply(bld, bld->dady[attrib][chan], bld->ystep);
+ bld->dadx[attrib][chan] = lp_build_mul_imm(&bld->base, bld->dadx[attrib][chan], bld->xstep);
+ bld->dady[attrib][chan] = lp_build_mul_imm(&bld->base, bld->dady[attrib][chan], bld->ystep);
}
}
}
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_sample_soa.c b/src/gallium/drivers/llvmpipe/lp_bld_sample_soa.c
index f7a030f..42e4ee6 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_sample_soa.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_sample_soa.c
@@ -309,7 +309,7 @@ lp_build_sample_2d_linear_aos(struct lp_build_sample_context *bld,
LLVMBuilderRef builder = bld->builder;
struct lp_build_context i32, h16, u8n;
LLVMTypeRef i32_vec_type, h16_vec_type, u8n_vec_type;
- LLVMValueRef f32_c256, i32_c8, i32_c128, i32_c255;
+ LLVMValueRef i32_c8, i32_c128, i32_c255;
LLVMValueRef s_ipart, s_fpart, s_fpart_lo, s_fpart_hi;
LLVMValueRef t_ipart, t_fpart, t_fpart_lo, t_fpart_hi;
LLVMValueRef x0, x1;
@@ -328,9 +328,8 @@ lp_build_sample_2d_linear_aos(struct lp_build_sample_context *bld,
h16_vec_type = lp_build_vec_type(h16.type);
u8n_vec_type = lp_build_vec_type(u8n.type);
- f32_c256 = lp_build_const_scalar(bld->coord_type, 256.0);
- s = lp_build_mul(&bld->coord_bld, s, f32_c256);
- t = lp_build_mul(&bld->coord_bld, t, f32_c256);
+ s = lp_build_mul_imm(&bld->coord_bld, s, 256);
+ t = lp_build_mul_imm(&bld->coord_bld, t, 256);
s = LLVMBuildFPToSI(builder, s, i32_vec_type, "");
t = LLVMBuildFPToSI(builder, t, i32_vec_type, "");
More information about the mesa-commit
mailing list