From 9b19a933192da8c595aa069e32b12abb3a0ddd60 Mon Sep 17 00:00:00 2001
From: Rhys Perry <pendingchaos02@gmail.com>
Date: Wed, 23 Nov 2022 20:46:59 +0000
Subject: [PATCH] ac/nir: combine shift translation
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Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Mihai Preda <mhpreda@gmail.com>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19966>
---
 src/amd/llvm/ac_nir_to_llvm.c | 42 +++++++++++++----------------------
 1 file changed, 15 insertions(+), 27 deletions(-)

diff --git a/src/amd/llvm/ac_nir_to_llvm.c b/src/amd/llvm/ac_nir_to_llvm.c
index b0410b594b0..6431ae63a0e 100644
--- a/src/amd/llvm/ac_nir_to_llvm.c
+++ b/src/amd/llvm/ac_nir_to_llvm.c
@@ -713,32 +713,8 @@ static bool visit_alu(struct ac_nir_context *ctx, const nir_alu_instr *instr)
    case nir_op_ixor:
       result = LLVMBuildXor(ctx->ac.builder, src[0], src[1], "");
       break;
-   case nir_op_ishl: {
-      if (ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[1])) <
-          ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])))
-         src[1] = LLVMBuildZExt(ctx->ac.builder, src[1], LLVMTypeOf(src[0]), "");
-      else if (ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[1])) >
-               ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])))
-         src[1] = LLVMBuildTrunc(ctx->ac.builder, src[1], LLVMTypeOf(src[0]), "");
-      LLVMTypeRef type = LLVMTypeOf(src[0]);
-      src[1] = LLVMBuildAnd(ctx->ac.builder, src[1],
-                            LLVMConstInt(type, LLVMGetIntTypeWidth(type) - 1, false), "");
-      result = LLVMBuildShl(ctx->ac.builder, src[0], src[1], "");
-      break;
-   }
-   case nir_op_ishr: {
-      if (ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[1])) <
-          ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])))
-         src[1] = LLVMBuildZExt(ctx->ac.builder, src[1], LLVMTypeOf(src[0]), "");
-      else if (ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[1])) >
-               ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])))
-         src[1] = LLVMBuildTrunc(ctx->ac.builder, src[1], LLVMTypeOf(src[0]), "");
-      LLVMTypeRef type = LLVMTypeOf(src[0]);
-      src[1] = LLVMBuildAnd(ctx->ac.builder, src[1],
-                            LLVMConstInt(type, LLVMGetIntTypeWidth(type) - 1, false), "");
-      result = LLVMBuildAShr(ctx->ac.builder, src[0], src[1], "");
-      break;
-   }
+   case nir_op_ishl:
+   case nir_op_ishr:
    case nir_op_ushr: {
       if (ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[1])) <
           ac_get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])))
@@ -749,7 +725,19 @@ static bool visit_alu(struct ac_nir_context *ctx, const nir_alu_instr *instr)
       LLVMTypeRef type = LLVMTypeOf(src[0]);
       src[1] = LLVMBuildAnd(ctx->ac.builder, src[1],
                             LLVMConstInt(type, LLVMGetIntTypeWidth(type) - 1, false), "");
-      result = LLVMBuildLShr(ctx->ac.builder, src[0], src[1], "");
+      switch (instr->op) {
+      case nir_op_ishl:
+         result = LLVMBuildShl(ctx->ac.builder, src[0], src[1], "");
+         break;
+      case nir_op_ishr:
+         result = LLVMBuildAShr(ctx->ac.builder, src[0], src[1], "");
+         break;
+      case nir_op_ushr:
+         result = LLVMBuildLShr(ctx->ac.builder, src[0], src[1], "");
+         break;
+      default:
+         break;
+      }
       break;
    }
    case nir_op_ilt: