From: Marek Olšák <marek.ol...@amd.com> The previous version has precision issues. This can be a problem with tessellation. Sadly, I can't find the article where I read it anymore. I'm not sure if the unsafe-fp-math flag would be enough to revert this. --- src/gallium/auxiliary/gallivm/lp_bld_tgsi_action.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_action.c b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_action.c index 0ad78b0..512558b 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_action.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_action.c @@ -538,12 +538,13 @@ lrp_emit( struct lp_build_tgsi_context * bld_base, struct lp_build_emit_data * emit_data) { - LLVMValueRef tmp; - tmp = lp_build_emit_llvm_binary(bld_base, TGSI_OPCODE_SUB, - emit_data->args[1], - emit_data->args[2]); - emit_data->output[emit_data->chan] = lp_build_emit_llvm_ternary(bld_base, - TGSI_OPCODE_MAD, emit_data->args[0], tmp, emit_data->args[2]); + struct lp_build_context *bld = &bld_base->base; + LLVMValueRef inv, a, b; + + inv = lp_build_sub(bld, bld_base->base.one, emit_data->args[0]); + a = lp_build_mul(bld, emit_data->args[1], emit_data->args[0]); + b = lp_build_mul(bld, emit_data->args[2], inv); + emit_data->output[emit_data->chan] = lp_build_add(bld, a, b); } /* TGSI_OPCODE_MAD */ -- 2.1.4 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev