summaryrefslogtreecommitdiff
path: root/src/gallium/drivers/llvmpipe/lp_bld_arit.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/gallium/drivers/llvmpipe/lp_bld_arit.c')
-rw-r--r--src/gallium/drivers/llvmpipe/lp_bld_arit.c11
1 files changed, 6 insertions, 5 deletions
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_arit.c b/src/gallium/drivers/llvmpipe/lp_bld_arit.c
index 9c59677a74..eea6b5d6a5 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_arit.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_arit.c
@@ -629,7 +629,8 @@ lp_build_abs(struct lp_build_context *bld,
if(type.floating) {
/* Mask out the sign bit */
LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
- LLVMValueRef mask = lp_build_int_const_scalar(type, ((unsigned long long)1 << type.width) - 1);
+ unsigned long absMask = ~(1 << (type.width - 1));
+ LLVMValueRef mask = lp_build_int_const_scalar(type, ((unsigned long long) absMask));
a = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
a = LLVMBuildAnd(bld->builder, a, mask, "");
a = LLVMBuildBitCast(bld->builder, a, vec_type, "");
@@ -1083,7 +1084,7 @@ lp_build_log(struct lp_build_context *bld,
LLVMValueRef x)
{
/* log(2) */
- LLVMValueRef log2 = lp_build_const_scalar(bld->type, 1.4426950408889634);
+ LLVMValueRef log2 = lp_build_const_scalar(bld->type, 0.69314718055994529);
return lp_build_mul(bld, log2, lp_build_exp2(bld, x));
}
@@ -1095,7 +1096,7 @@ lp_build_log(struct lp_build_context *bld,
/**
* Generate polynomial.
- * Ex: x^2 * coeffs[0] + x * coeffs[1] + coeffs[2].
+ * Ex: coeffs[0] + x * coeffs[1] + x^2 * coeffs[2].
*/
static LLVMValueRef
lp_build_polynomial(struct lp_build_context *bld,
@@ -1285,13 +1286,13 @@ lp_build_log2_approx(struct lp_build_context *bld,
/* mant = (float) mantissa(x) */
mant = LLVMBuildAnd(bld->builder, i, mantmask, "");
mant = LLVMBuildOr(bld->builder, mant, one, "");
- mant = LLVMBuildSIToFP(bld->builder, mant, vec_type, "");
+ mant = LLVMBuildBitCast(bld->builder, mant, vec_type, "");
logmant = lp_build_polynomial(bld, mant, lp_build_log2_polynomial,
Elements(lp_build_log2_polynomial));
/* This effectively increases the polynomial degree by one, but ensures that log2(1) == 0*/
- logmant = LLVMBuildMul(bld->builder, logmant, LLVMBuildMul(bld->builder, mant, bld->one, ""), "");
+ logmant = LLVMBuildMul(bld->builder, logmant, LLVMBuildSub(bld->builder, mant, bld->one, ""), "");
res = LLVMBuildAdd(bld->builder, logmant, logexp, "");
}