diff options
| author | Brian Paul <[email protected]> | 2010-10-13 12:35:38 -0600 |
|---|---|---|
| committer | Brian Paul <[email protected]> | 2010-10-13 12:37:42 -0600 |
| commit | e487b665aa6f3d6f290916d1205107dd2dea971d (patch) | |
| tree | 43d02391d80304bec51e04ee258d33c348dbefa3 | |
| parent | bee22ed6b9425fa4681211e84d0a61467975195f (diff) | |
gallivm: work-around trilinear mipmap filtering regression with LLVM 2.8
The bug only happens on the AOS / fixed-pt path.
| -rw-r--r-- | src/gallium/auxiliary/gallivm/lp_bld_sample_aos.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_sample_aos.c b/src/gallium/auxiliary/gallivm/lp_bld_sample_aos.c index 641d24b5b6d..d3e3b242af4 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_sample_aos.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_sample_aos.c @@ -873,6 +873,26 @@ lp_build_sample_mipmap(struct lp_build_sample_context *bld, lod_fpart = LLVMBuildTrunc(builder, lod_fpart, h16_bld.elem_type, ""); lod_fpart = lp_build_broadcast_scalar(&h16_bld, lod_fpart); +#if HAVE_LLVM == 0x208 + /* This is a work-around for a bug in LLVM 2.8. + * Evidently, something goes wrong in the construction of the + * lod_fpart short[8] vector. Adding this no-effect shuffle seems + * to force the vector to be properly constructed. + * Tested with mesa-demos/src/tests/mipmap_limits.c (press t, f). + */ + { + LLVMValueRef shuffles[8], shuffle; + int i; + assert(h16_bld.type.length <= Elements(shuffles)); + for (i = 0; i < h16_bld.type.length; i++) + shuffles[i] = lp_build_const_int32(2 * (i & 1)); + shuffle = LLVMConstVector(shuffles, h16_bld.type.length); + lod_fpart = LLVMBuildShuffleVector(builder, + lod_fpart, lod_fpart, + shuffle, ""); + } +#endif + colors0_lo = lp_build_lerp(&h16_bld, lod_fpart, colors0_lo, colors1_lo); colors0_hi = lp_build_lerp(&h16_bld, lod_fpart, |