aco/optimizer: copy propagate to output modifier instructions

Foz-DB Navi21:
Totals from 847 (1.11% of 76572) affected shaders:
Instrs: 2331245 -> 2330335 (-0.04%); split: -0.04%, +0.00%
CodeSize: 12451040 -> 12451736 (+0.01%); split: -0.00%, +0.01%
Latency: 26230953 -> 26229153 (-0.01%); split: -0.01%, +0.00%
InvThroughput: 6297802 -> 6296788 (-0.02%); split: -0.02%, +0.00%
VClause: 64527 -> 64528 (+0.00%); split: -0.00%, +0.01%
SClause: 73150 -> 73121 (-0.04%); split: -0.06%, +0.02%
Copies: 180083 -> 179172 (-0.51%); split: -0.53%, +0.02%
PreSGPRs: 62311 -> 62316 (+0.01%)
PreVGPRs: 51720 -> 51710 (-0.02%)

Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25347>

src/amd/compiler/aco_optimizer.cpp

@@ -298,6 +298,8 @@ struct ssa_info {
 
    void set_omod2(Instruction* mul)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_omod2);
       instr = mul;
    }
@@ -306,6 +308,8 @@ struct ssa_info {
 
    void set_omod4(Instruction* mul)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_omod4);
       instr = mul;
    }
@@ -314,6 +318,8 @@ struct ssa_info {
 
    void set_omod5(Instruction* mul)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_omod5);
       instr = mul;
    }
@@ -322,6 +328,8 @@ struct ssa_info {
 
    void set_clamp(Instruction* med3)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_clamp);
       instr = med3;
    }
@@ -330,6 +338,8 @@ struct ssa_info {
 
    void set_f2f16(Instruction* conv)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_f2f16);
       instr = conv;
    }
@@ -466,6 +476,8 @@ struct ssa_info {
 
    void set_insert(Instruction* insert)
    {
+      if (label & temp_labels)
+         return;
       add_label(label_insert);
       instr = insert;
    }