[dynarmic] add back A64 identity pass (#3519)

results in way better codegen (less noise for movs and all dat)
i think it was removed by accident by me, oops

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3519
Reviewed-by: DraVee <dravee@eden-emu.dev>
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Co-authored-by: lizzie <lizzie@eden-emu.dev>
Co-committed-by: lizzie <lizzie@eden-emu.dev>

src/dynarmic/src/dynarmic/ir/opt_passes.cpp

@@ -1472,11 +1472,11 @@ static void VerificationPass(const IR::Block& block) {
 void Optimize(IR::Block& block, const A32::UserConfig& conf, const Optimization::PolyfillOptions& polyfill_options) {
     Optimization::PolyfillPass(block, polyfill_options);
     Optimization::NamingPass(block);
-    if (conf.HasOptimization(OptimizationFlag::GetSetElimination)) [[likely]] {
+    if (conf.HasOptimization(OptimizationFlag::GetSetElimination)) {
         Optimization::A32GetSetElimination(block, {.convert_nzc_to_nz = true});
         Optimization::DeadCodeElimination(block);
     }
-    if (conf.HasOptimization(OptimizationFlag::ConstProp)) [[likely]] {
+    if (conf.HasOptimization(OptimizationFlag::ConstProp)) {
         Optimization::ConstantMemoryReads(block, conf.callbacks);
         Optimization::ConstantPropagation(block);
         Optimization::DeadCodeElimination(block);
@@ -1491,17 +1491,18 @@ void Optimize(IR::Block& block, const A64::UserConfig& conf, const Optimization:
     Optimization::PolyfillPass(block, polyfill_options);
     Optimization::A64CallbackConfigPass(block, conf);
     Optimization::NamingPass(block);
-    if (conf.HasOptimization(OptimizationFlag::GetSetElimination) && !conf.check_halt_on_memory_access) [[likely]] {
+    if (conf.HasOptimization(OptimizationFlag::GetSetElimination) && !conf.check_halt_on_memory_access) {
         Optimization::A64GetSetElimination(block);
         Optimization::DeadCodeElimination(block);
     }
-    if (conf.HasOptimization(OptimizationFlag::ConstProp)) [[likely]] {
+    if (conf.HasOptimization(OptimizationFlag::ConstProp)) {
         Optimization::ConstantPropagation(block);
         Optimization::DeadCodeElimination(block);
     }
-    if (conf.HasOptimization(OptimizationFlag::MiscIROpt)) [[likely]] {
+    if (conf.HasOptimization(OptimizationFlag::MiscIROpt)) {
         Optimization::A64MergeInterpretBlocksPass(block, conf.callbacks);
     }
+    Optimization::IdentityRemovalPass(block);
     if (!conf.HasOptimization(OptimizationFlag::DisableVerification)) {
         Optimization::VerificationPass(block);
     }