From 0f27368fdab3d2d1169e8dab14854e888bc9ce72 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Tue, 26 Jan 2021 23:41:21 +0000
Subject: [PATCH] A64: Add hook_isb option

---
 include/dynarmic/A64/config.h    |  6 ++++++
 src/backend/x64/a64_emit_x64.cpp | 10 ++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/include/dynarmic/A64/config.h b/include/dynarmic/A64/config.h
index e6f48ef6..6a029d97 100644
--- a/include/dynarmic/A64/config.h
+++ b/include/dynarmic/A64/config.h
@@ -110,6 +110,7 @@ struct UserCallbacks {
 
     virtual void ExceptionRaised(VAddr pc, Exception exception) = 0;
     virtual void DataCacheOperationRaised(DataCacheOperation /*op*/, VAddr /*value*/) {}
+    virtual void InstructionSynchronizationBarrierRaised() {}
 
     // Timing-related callbacks
     // ticks ticks have passed
@@ -153,6 +154,11 @@ struct UserConfig {
     /// Executing DC ZVA in this mode will result in zeros being written to memory.
     bool hook_data_cache_operations = false;
 
+    /// When set to true, UserCallbacks::InstructionSynchronizationBarrierRaised will be
+    /// called when an ISB instruction is executed.
+    /// When set to false, ISB will be treated as a NOP instruction.
+    bool hook_isb = false;
+
     /// When set to true, UserCallbacks::ExceptionRaised will be called when any hint
     /// instruction is executed.
     bool hook_hint_instructions = false;
diff --git a/src/backend/x64/a64_emit_x64.cpp b/src/backend/x64/a64_emit_x64.cpp
index c8be6fe1..c89f4e91 100644
--- a/src/backend/x64/a64_emit_x64.cpp
+++ b/src/backend/x64/a64_emit_x64.cpp
@@ -659,11 +659,13 @@ void A64EmitX64::EmitA64DataMemoryBarrier(A64EmitContext&, IR::Inst*) {
     code.lfence();
 }
 
-void A64EmitX64::EmitA64InstructionSynchronizationBarrier(A64EmitContext& ctx, IR::Inst* ) {
-    ctx.reg_alloc.HostCall(nullptr);
+void A64EmitX64::EmitA64InstructionSynchronizationBarrier(A64EmitContext& ctx, IR::Inst*) {
+    if (!conf.hook_isb) {
+        return;
+    }
 
-    code.mov(code.ABI_PARAM1, reinterpret_cast<u64>(jit_interface));
-    code.CallLambda([](A64::Jit* jit) { jit->ClearCache(); });
+    ctx.reg_alloc.HostCall(nullptr);
+    Devirtualize<&A64::UserCallbacks::InstructionSynchronizationBarrierRaised>(conf.callbacks).EmitCall(code);
 }
 
 void A64EmitX64::EmitA64GetCNTFRQ(A64EmitContext& ctx, IR::Inst* inst) {