From 6d383159d405b0cf9c9c03eaeea4ed46aa2b1d29 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daniel@schuermann.dev>
Date: Wed, 30 Mar 2022 18:01:45 +0200
Subject: [PATCH] aco/optimizer: check recursively if we can eliminate s_and
 exec
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Totals from 2860 (2.12% of 134913) affected shaders: (GFX10.3)
CodeSize: 5990728 -> 5979164 (-0.19%); split: -0.20%, +0.01%
Instrs: 1094562 -> 1091653 (-0.27%); split: -0.28%, +0.01%
Latency: 8689841 -> 8684523 (-0.06%); split: -0.07%, +0.00%
InvThroughput: 1840533 -> 1840527 (-0.00%); split: -0.00%, +0.00%
SClause: 51437 -> 51439 (+0.00%)
Copies: 82461 -> 82472 (+0.01%)
PreSGPRs: 83136 -> 83172 (+0.04%)

Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15675>
---
 src/amd/compiler/aco_optimizer.cpp | 39 +++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/src/amd/compiler/aco_optimizer.cpp b/src/amd/compiler/aco_optimizer.cpp
index 56af25a11f7..5ac2ebc7335 100644
--- a/src/amd/compiler/aco_optimizer.cpp
+++ b/src/amd/compiler/aco_optimizer.cpp
@@ -1149,6 +1149,27 @@ can_eliminate_fcanonicalize(opt_ctx& ctx, aco_ptr<Instruction>& instr, Temp tmp)
    return instr_info.can_use_input_modifiers[(int)op] && does_fp_op_flush_denorms(ctx, op);
 }
 
+bool
+can_eliminate_and_exec(opt_ctx& ctx, Temp tmp, unsigned pass_flags)
+{
+   if (ctx.info[tmp.id()].is_vopc()) {
+      Instruction* vopc_instr = ctx.info[tmp.id()].instr;
+      /* Remove superfluous s_and when the VOPC instruction uses the same exec and thus
+       * already produces the same result */
+      return vopc_instr->pass_flags == pass_flags;
+   }
+   if (ctx.info[tmp.id()].is_bitwise()) {
+      Instruction* instr = ctx.info[tmp.id()].instr;
+      if (instr->pass_flags != pass_flags)
+         return false;
+      return std::all_of(
+         instr->operands.begin(), instr->operands.end(),
+         [&](const Operand& op)
+         { return op.isTemp() && can_eliminate_and_exec(ctx, op.getTemp(), pass_flags); });
+   }
+   return false;
+}
+
 bool
 is_copy_label(opt_ctx& ctx, aco_ptr<Instruction>& instr, ssa_info& info)
 {
@@ -1802,16 +1823,9 @@ label_instruction(opt_ctx& ctx, aco_ptr<Instruction>& instr)
              * s_and is unnecessary. */
             ctx.info[instr->definitions[0].tempId()].set_temp(instr->operands[0].getTemp());
             break;
-         } else if (ctx.info[instr->operands[0].tempId()].is_vopc()) {
-            Instruction* vopc_instr = ctx.info[instr->operands[0].tempId()].instr;
-            /* Remove superfluous s_and when the VOPC instruction uses the same exec and thus
-             * already produces the same result */
-            if (vopc_instr->pass_flags == instr->pass_flags) {
-               assert(instr->pass_flags > 0);
-               ctx.info[instr->definitions[0].tempId()].set_temp(
-                  vopc_instr->definitions[0].getTemp());
-               break;
-            }
+         } else if (can_eliminate_and_exec(ctx, instr->operands[0].getTemp(), instr->pass_flags)) {
+            ctx.info[instr->definitions[0].tempId()].set_temp(instr->operands[0].getTemp());
+            break;
          }
       }
       FALLTHROUGH;
@@ -1827,14 +1841,15 @@ label_instruction(opt_ctx& ctx, aco_ptr<Instruction>& instr)
                       })) {
          ctx.info[instr->definitions[0].tempId()].set_uniform_bitwise();
       }
-      FALLTHROUGH;
+      ctx.info[instr->definitions[0].tempId()].set_bitwise(instr.get());
+      break;
    case aco_opcode::s_lshl_b32:
    case aco_opcode::v_or_b32:
    case aco_opcode::v_lshlrev_b32:
    case aco_opcode::v_bcnt_u32_b32:
    case aco_opcode::v_and_b32:
    case aco_opcode::v_xor_b32:
-      ctx.info[instr->definitions[0].tempId()].set_bitwise(instr.get());
+      ctx.info[instr->definitions[0].tempId()].set_usedef(instr.get());
       break;
    case aco_opcode::v_min_f32:
    case aco_opcode::v_min_f16: