LLVMValueRef a)
{
const struct lp_type type = bld->type;
- LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
+ LLVMTypeRef int_vec_type = bld->int_vec_type;
LLVMValueRef res;
assert(type.floating);
res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_NEAREST);
}
else {
- LLVMTypeRef vec_type = lp_build_vec_type(type);
- LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
- LLVMValueRef sign;
LLVMValueRef half;
- /* get sign bit */
- sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
- sign = LLVMBuildAnd(bld->builder, sign, mask, "");
-
- /* sign * 0.5 */
half = lp_build_const_vec(type, 0.5);
- half = LLVMBuildBitCast(bld->builder, half, int_vec_type, "");
- half = LLVMBuildOr(bld->builder, sign, half, "");
- half = LLVMBuildBitCast(bld->builder, half, vec_type, "");
+
+ if (type.sign) {
+ LLVMTypeRef vec_type = bld->vec_type;
+ LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
+ LLVMValueRef sign;
+
+ /* get sign bit */
+ sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
+ sign = LLVMBuildAnd(bld->builder, sign, mask, "");
+
+ /* sign * 0.5 */
+ half = LLVMBuildBitCast(bld->builder, half, int_vec_type, "");
+ half = LLVMBuildOr(bld->builder, sign, half, "");
+ half = LLVMBuildBitCast(bld->builder, half, vec_type, "");
+ }
res = LLVMBuildFAdd(bld->builder, a, half, "");
}
LLVMValueRef a)
{
const struct lp_type type = bld->type;
- LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
+ LLVMTypeRef int_vec_type = bld->int_vec_type;
LLVMValueRef res;
assert(type.floating);
res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_FLOOR);
}
else {
- /* Take the sign bit and add it to 1 constant */
- LLVMTypeRef vec_type = lp_build_vec_type(type);
- unsigned mantissa = lp_mantissa(type);
- LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
- LLVMValueRef sign;
- LLVMValueRef offset;
-
- /* sign = a < 0 ? ~0 : 0 */
- sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
- sign = LLVMBuildAnd(bld->builder, sign, mask, "");
- sign = LLVMBuildAShr(bld->builder, sign, lp_build_const_int_vec(type, type.width - 1), "ifloor.sign");
-
- /* offset = -0.99999(9)f */
- offset = lp_build_const_vec(type, -(double)(((unsigned long long)1 << mantissa) - 10)/((unsigned long long)1 << mantissa));
- offset = LLVMConstBitCast(offset, int_vec_type);
-
- /* offset = a < 0 ? offset : 0.0f */
- offset = LLVMBuildAnd(bld->builder, offset, sign, "");
- offset = LLVMBuildBitCast(bld->builder, offset, vec_type, "ifloor.offset");
-
- res = LLVMBuildFAdd(bld->builder, a, offset, "ifloor.res");
+ res = a;
+
+ if (type.sign) {
+ /* Take the sign bit and add it to 1 constant */
+ LLVMTypeRef vec_type = bld->vec_type;
+ unsigned mantissa = lp_mantissa(type);
+ LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
+ LLVMValueRef sign;
+ LLVMValueRef offset;
+
+ /* sign = a < 0 ? ~0 : 0 */
+ sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
+ sign = LLVMBuildAnd(bld->builder, sign, mask, "");
+ sign = LLVMBuildAShr(bld->builder, sign, lp_build_const_int_vec(type, type.width - 1), "ifloor.sign");
+
+ /* offset = -0.99999(9)f */
+ offset = lp_build_const_vec(type, -(double)(((unsigned long long)1 << mantissa) - 10)/((unsigned long long)1 << mantissa));
+ offset = LLVMConstBitCast(offset, int_vec_type);
+
+ /* offset = a < 0 ? offset : 0.0f */
+ offset = LLVMBuildAnd(bld->builder, offset, sign, "");
+ offset = LLVMBuildBitCast(bld->builder, offset, vec_type, "ifloor.offset");
+
+ res = LLVMBuildFAdd(bld->builder, res, offset, "ifloor.res");
+ }
}
/* round to nearest (toward zero) */
LLVMValueRef a)
{
const struct lp_type type = bld->type;
- LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
+ LLVMTypeRef int_vec_type = bld->int_vec_type;
LLVMValueRef res;
assert(type.floating);
res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_CEIL);
}
else {
- LLVMTypeRef vec_type = lp_build_vec_type(type);
+ LLVMTypeRef vec_type = bld->vec_type;
unsigned mantissa = lp_mantissa(type);
- LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
- LLVMValueRef sign;
LLVMValueRef offset;
- /* sign = a < 0 ? 0 : ~0 */
- sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
- sign = LLVMBuildAnd(bld->builder, sign, mask, "");
- sign = LLVMBuildAShr(bld->builder, sign, lp_build_const_int_vec(type, type.width - 1), "iceil.sign");
- sign = LLVMBuildNot(bld->builder, sign, "iceil.not");
-
/* offset = 0.99999(9)f */
offset = lp_build_const_vec(type, (double)(((unsigned long long)1 << mantissa) - 10)/((unsigned long long)1 << mantissa));
- offset = LLVMConstBitCast(offset, int_vec_type);
- /* offset = a < 0 ? 0.0 : offset */
- offset = LLVMBuildAnd(bld->builder, offset, sign, "");
- offset = LLVMBuildBitCast(bld->builder, offset, vec_type, "iceil.offset");
+ if (type.sign) {
+ LLVMValueRef mask = lp_build_const_int_vec(type, (unsigned long long)1 << (type.width - 1));
+ LLVMValueRef sign;
+
+ /* sign = a < 0 ? 0 : ~0 */
+ sign = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
+ sign = LLVMBuildAnd(bld->builder, sign, mask, "");
+ sign = LLVMBuildAShr(bld->builder, sign, lp_build_const_int_vec(type, type.width - 1), "iceil.sign");
+ sign = LLVMBuildNot(bld->builder, sign, "iceil.not");
+
+ /* offset = a < 0 ? 0.0 : offset */
+ offset = LLVMConstBitCast(offset, int_vec_type);
+ offset = LLVMBuildAnd(bld->builder, offset, sign, "");
+ offset = LLVMBuildBitCast(bld->builder, offset, vec_type, "iceil.offset");
+ }
res = LLVMBuildFAdd(bld->builder, a, offset, "iceil.res");
}
lp_build_log2_approx(bld, x, NULL, NULL, &res);
return res;
}
+
+
+/**
+ * Faster (and less accurate) log2.
+ *
+ * log2(x) = floor(log2(x)) + frac(x)
+ *
+ * See http://www.flipcode.com/archives/Fast_log_Function.shtml
+ */
+LLVMValueRef
+lp_build_fast_log2(struct lp_build_context *bld,
+ LLVMValueRef x)
+{
+ const struct lp_type type = bld->type;
+ LLVMTypeRef vec_type = bld->vec_type;
+ LLVMTypeRef int_vec_type = bld->int_vec_type;
+
+ unsigned mantissa = lp_mantissa(type);
+ LLVMValueRef mantmask = lp_build_const_int_vec(type, (1ULL << mantissa) - 1);
+ LLVMValueRef one = LLVMConstBitCast(bld->one, int_vec_type);
+
+ LLVMValueRef ipart;
+ LLVMValueRef fpart;
+
+ assert(lp_check_value(bld->type, x));
+
+ assert(type.floating);
+
+ x = LLVMBuildBitCast(bld->builder, x, int_vec_type, "");
+
+ /* ipart = floor(log2(x)) - 1 */
+ ipart = LLVMBuildLShr(bld->builder, x, lp_build_const_int_vec(type, mantissa), "");
+ ipart = LLVMBuildAnd(bld->builder, ipart, lp_build_const_int_vec(type, 255), "");
+ ipart = LLVMBuildSub(bld->builder, ipart, lp_build_const_int_vec(type, 128), "");
+ ipart = LLVMBuildSIToFP(bld->builder, ipart, vec_type, "");
+
+ /* fpart = 1.0 + frac(x) */
+ fpart = LLVMBuildAnd(bld->builder, x, mantmask, "");
+ fpart = LLVMBuildOr(bld->builder, fpart, one, "");
+ fpart = LLVMBuildBitCast(bld->builder, fpart, vec_type, "");
+
+ /* floor(log2(x)) + frac(x) */
+ return LLVMBuildFAdd(bld->builder, ipart, fpart, "");
+}