From: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Date: Fri, 19 Jun 2020 16:33:32 +0000 (+0200)
Subject: ac/llvm: remove the -1 hack from ac_atomic_inc_wrap
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=438392243fb284884e8499758064256fb3dad48d;p=mesa.git

ac/llvm: remove the -1 hack from ac_atomic_inc_wrap

To match the behavior of proprietary drivers.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5688>
---

diff --git a/src/amd/llvm/ac_nir_to_llvm.c b/src/amd/llvm/ac_nir_to_llvm.c
index bd3cc246e5c..862ae5c30ff 100644
--- a/src/amd/llvm/ac_nir_to_llvm.c
+++ b/src/amd/llvm/ac_nir_to_llvm.c
@@ -3032,16 +3032,6 @@ static LLVMValueRef visit_image_atomic(struct ac_nir_context *ctx,
 	case nir_intrinsic_image_deref_atomic_inc_wrap: {
 		atomic_name = "inc";
 		atomic_subop = ac_atomic_inc_wrap;
-		/* ATOMIC_INC instruction does:
-		 *      value = (value + 1) % (data + 1)
-		 * but we want:
-		 *      value = (value + 1) % data
-		 * So replace 'data' by 'data - 1'.
-		 */
-		ctx->ssa_defs[instr->src[3].ssa->index] =
-			LLVMBuildSub(ctx->ac.builder,
-				     ctx->ssa_defs[instr->src[3].ssa->index],
-				     ctx->ac.i32_1, "");
 		break;
 	}
 	case nir_intrinsic_bindless_image_atomic_dec_wrap: