diff options
| -rw-r--r-- | src/amd/common/ac_llvm_build.c | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/src/amd/common/ac_llvm_build.c b/src/amd/common/ac_llvm_build.c index 6c010e8c3a6..8a329515b57 100644 --- a/src/amd/common/ac_llvm_build.c +++ b/src/amd/common/ac_llvm_build.c @@ -498,8 +498,35 @@ ac_prepare_cube_coords(struct ac_llvm_context *ctx, LLVMValueRef invma; if (is_array && !is_lod) { - coords_arg[3] = ac_build_intrinsic(ctx, "llvm.rint.f32", ctx->f32, - &coords_arg[3], 1, 0); + LLVMValueRef tmp = coords_arg[3]; + tmp = ac_build_intrinsic(ctx, "llvm.rint.f32", ctx->f32, &tmp, 1, 0); + + /* Section 8.9 (Texture Functions) of the GLSL 4.50 spec says: + * + * "For Array forms, the array layer used will be + * + * max(0, min(d−1, floor(layer+0.5))) + * + * where d is the depth of the texture array and layer + * comes from the component indicated in the tables below. + * Workaroudn for an issue where the layer is taken from a + * helper invocation which happens to fall on a different + * layer due to extrapolation." + * + * VI and earlier attempt to implement this in hardware by + * clamping the value of coords[2] = (8 * layer) + face. + * Unfortunately, this means that the we end up with the wrong + * face when clamping occurs. + * + * Clamp the layer earlier to work around the issue. + */ + if (ctx->chip_class <= VI) { + LLVMValueRef ge0; + ge0 = LLVMBuildFCmp(builder, LLVMRealOGE, tmp, ctx->f32_0, ""); + tmp = LLVMBuildSelect(builder, ge0, tmp, ctx->f32_0, ""); + } + + coords_arg[3] = tmp; } build_cube_intrinsic(ctx, coords_arg, &selcoords); |