+ 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);