diff options
| -rw-r--r-- | src/gallium/auxiliary/gallivm/lp_bld_sample.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_sample.c b/src/gallium/auxiliary/gallivm/lp_bld_sample.c index 19e380a8dc..44f44ff1aa 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_sample.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_sample.c @@ -655,11 +655,21 @@ lp_build_sample_partial_offset(struct lp_build_context *bld, * Pixel blocks have power of two dimensions. LLVM should convert the * rem/div to bit arithmetic. * TODO: Verify this. + * It does indeed BUT it does transform it to scalar (and back) when doing so + * (using roughly extract, shift/and, mov, unpack) (llvm 2.7). + * The generated code looks seriously unfunny and is quite expensive. */ - +#if 0 LLVMValueRef block_width = lp_build_const_int_vec(bld->type, block_length); subcoord = LLVMBuildURem(bld->builder, coord, block_width, ""); coord = LLVMBuildUDiv(bld->builder, coord, block_width, ""); +#else + unsigned logbase2 = util_unsigned_logbase2(block_length); + LLVMValueRef block_shift = lp_build_const_int_vec(bld->type, logbase2); + LLVMValueRef block_mask = lp_build_const_int_vec(bld->type, block_length - 1); + subcoord = LLVMBuildAnd(bld->builder, coord, block_mask, ""); + coord = LLVMBuildLShr(bld->builder, coord, block_shift, ""); +#endif } offset = lp_build_mul(bld, coord, stride); |