From 7a2083b6032fa989b45087fc0c013db4f9e38885 Mon Sep 17 00:00:00 2001
From: Merry <git@mary.rs>
Date: Sun, 11 Dec 2022 17:32:37 +0000
Subject: [PATCH] exception_handler: Minimize arm64 FakeCall

---
 src/dynarmic/backend/arm64/emit_arm64_memory.cpp |  2 --
 src/dynarmic/backend/exception_handler.h         |  4 ----
 src/dynarmic/backend/exception_handler_posix.cpp | 13 +------------
 3 files changed, 1 insertion(+), 18 deletions(-)

diff --git a/src/dynarmic/backend/arm64/emit_arm64_memory.cpp b/src/dynarmic/backend/arm64/emit_arm64_memory.cpp
index 1f36a7a0..4aff79f2 100644
--- a/src/dynarmic/backend/arm64/emit_arm64_memory.cpp
+++ b/src/dynarmic/backend/arm64/emit_arm64_memory.cpp
@@ -503,7 +503,6 @@ void FastmemEmitReadMemory(oaknut::CodeGenerator& code, EmitContext& ctx, IR::In
                 .marker = marker,
                 .fc = FakeCall{
                     .call_pc = mcl::bit_cast<u64>(code.ptr<void*>()),
-                    .ret_pc = 0,
                 },
                 .recompile = ctx.conf.recompile_on_fastmem_failure,
             });
@@ -554,7 +553,6 @@ void FastmemEmitWriteMemory(oaknut::CodeGenerator& code, EmitContext& ctx, IR::I
                 .marker = marker,
                 .fc = FakeCall{
                     .call_pc = mcl::bit_cast<u64>(code.ptr<void*>()),
-                    .ret_pc = 0,
                 },
                 .recompile = ctx.conf.recompile_on_fastmem_failure,
             });
diff --git a/src/dynarmic/backend/exception_handler.h b/src/dynarmic/backend/exception_handler.h
index 2268297e..179433ba 100644
--- a/src/dynarmic/backend/exception_handler.h
+++ b/src/dynarmic/backend/exception_handler.h
@@ -34,10 +34,6 @@ struct FakeCall {
 #elif defined(MCL_ARCHITECTURE_ARM64)
 struct FakeCall {
     u64 call_pc;
-    u64 ret_pc;
-    std::optional<int> load_xscratch0;
-    std::optional<int> load_xscratch1;
-    std::optional<int> load_q0;
 };
 #else
 #    error "Invalid architecture"
diff --git a/src/dynarmic/backend/exception_handler_posix.cpp b/src/dynarmic/backend/exception_handler_posix.cpp
index eba2168f..eb7c02f8 100644
--- a/src/dynarmic/backend/exception_handler_posix.cpp
+++ b/src/dynarmic/backend/exception_handler_posix.cpp
@@ -178,7 +178,7 @@ void SigHandler::SigAction(int sig, siginfo_t* info, void* raw_context) {
 #        define CTX_LR (mctx.regs[30])
 #        define CTX_X(i) (mctx.regs[i])
 #        define CTX_Q(i) (fpctx->vregs[i])
-    const auto fpctx = [&mctx] {
+    [[maybe_unused]] const auto fpctx = [&mctx] {
         _aarch64_ctx* header = (_aarch64_ctx*)&mctx.__reserved;
         while (header->magic != FPSIMD_MAGIC) {
             ASSERT(header->magic && header->size);
@@ -203,19 +203,8 @@ void SigHandler::SigAction(int sig, siginfo_t* info, void* raw_context) {
         if (iter != sig_handler.code_block_infos.end()) {
             FakeCall fc = iter->cb(CTX_PC);
 
-            CTX_LR = fc.ret_pc;
             CTX_PC = fc.call_pc;
 
-            if (fc.load_xscratch0) {
-                CTX_X(Arm64::Xscratch0.index()) = CTX_X(*fc.load_xscratch0);
-            }
-            if (fc.load_xscratch1) {
-                CTX_X(Arm64::Xscratch1.index()) = CTX_X(*fc.load_xscratch1);
-            }
-            if (fc.load_q0) {
-                CTX_Q(0) = CTX_Q(*fc.load_q0);
-            }
-
             return;
         }
     }