emit_x64: Fix bugs in fast dispatcher

* We failed to invalidate entries if there are no patches required for a location descriptor.
* Bug in A64 hashing code (rbx instead of rbp).
* Bug in A32 and A64 lookup code (inconsistent choice of key: PC vs IR::LocationDescriptor).
* Test case added.

src/dynarmic/backend/x64/a32_emit_x64.cpp

@@ -235,8 +235,9 @@ void A32EmitX64::GenTerminalHandlers() {
         calculate_location_descriptor();
         code.L(rsb_cache_miss);
         code.mov(r12, reinterpret_cast<u64>(fast_dispatch_table.data()));
+        code.mov(rbp, rbx);
         if (code.HasHostFeature(HostFeature::SSE42)) {
-            code.crc32(ebp, r12d);
+            code.crc32(rbp, r12);
         }
         code.and_(ebp, fast_dispatch_table_mask);
         code.lea(rbp, ptr[r12 + rbp]);
@@ -254,11 +255,12 @@ void A32EmitX64::GenTerminalHandlers() {
         fast_dispatch_table_lookup = code.getCurr<FastDispatchEntry& (*)(u64)>();
         code.mov(code.ABI_PARAM2, reinterpret_cast<u64>(fast_dispatch_table.data()));
         if (code.HasHostFeature(HostFeature::SSE42)) {
-            code.crc32(code.ABI_PARAM1.cvt32(), code.ABI_PARAM2.cvt32());
+            code.crc32(code.ABI_PARAM1, code.ABI_PARAM2);
         }
         code.and_(code.ABI_PARAM1.cvt32(), fast_dispatch_table_mask);
         code.lea(code.ABI_RETURN, code.ptr[code.ABI_PARAM1 + code.ABI_PARAM2]);
         code.ret();
+        PerfMapRegister(fast_dispatch_table_lookup, code.getCurr(), "a32_fast_dispatch_table_lookup");
     }
 }
 

src/dynarmic/backend/x64/a64_emit_x64.cpp

@@ -193,8 +193,9 @@ void A64EmitX64::GenTerminalHandlers() {
         calculate_location_descriptor();
         code.L(rsb_cache_miss);
         code.mov(r12, reinterpret_cast<u64>(fast_dispatch_table.data()));
+        code.mov(rbp, rbx);
         if (code.HasHostFeature(HostFeature::SSE42)) {
-            code.crc32(rbx, r12d);
+            code.crc32(rbp, r12);
         }
         code.and_(ebp, fast_dispatch_table_mask);
         code.lea(rbp, ptr[r12 + rbp]);
@@ -215,7 +216,7 @@ void A64EmitX64::GenTerminalHandlers() {
             code.crc32(code.ABI_PARAM1, code.ABI_PARAM2);
         }
         code.and_(code.ABI_PARAM1.cvt32(), fast_dispatch_table_mask);
-        code.lea(code.ABI_RETURN, code.ptr[code.ABI_PARAM1 + code.ABI_PARAM2]);
+        code.lea(code.ABI_RETURN, code.ptr[code.ABI_PARAM2 + code.ABI_PARAM1]);
         code.ret();
         PerfMapRegister(fast_dispatch_table_lookup, code.getCurr(), "a64_fast_dispatch_table_lookup");
     }

src/dynarmic/backend/x64/emit_x64.cpp

@@ -325,7 +325,9 @@ void EmitX64::Patch(const IR::LocationDescriptor& target_desc, CodePtr target_co
 }
 
 void EmitX64::Unpatch(const IR::LocationDescriptor& target_desc) {
+    if (patch_information.count(target_desc)) {
         Patch(target_desc, nullptr);
+    }
 }
 
 void EmitX64::ClearCache() {
@@ -345,9 +347,8 @@ void EmitX64::InvalidateBasicBlocks(const tsl::robin_set<IR::LocationDescriptor>
             continue;
         }
 
-        if (patch_information.count(descriptor)) {
         Unpatch(descriptor);
-        }
+
         block_descriptors.erase(it);
     }
 }

tests/A64/test_invalidation.cpp

@@ -0,0 +1,113 @@
+/* This file is part of the dynarmic project.
+ * Copyright (c) 2018 MerryMage
+ * SPDX-License-Identifier: 0BSD
+ */
+
+#include <catch2/catch.hpp>
+
+#include "./testenv.h"
+#include "dynarmic/interface/A64/a64.h"
+
+using namespace Dynarmic;
+
+TEST_CASE("ensure fast dispatch entry is cleared even when a block does not have any patching requirements", "[a64]") {
+    A64TestEnv env;
+
+    A64::UserConfig conf{&env};
+    A64::Jit jit{conf};
+
+    REQUIRE(conf.HasOptimization(OptimizationFlag::FastDispatch));
+
+    env.code_mem_start_address = 100;
+    env.code_mem.clear();
+    env.code_mem.emplace_back(0xd2800d80);  // MOV X0, 108
+    env.code_mem.emplace_back(0xd61f0000);  // BR X0
+    env.code_mem.emplace_back(0xd2800540);  // MOV X0, 42
+    env.code_mem.emplace_back(0x14000000);  // B .
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.InvalidateCacheRange(108, 4);
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    env.code_mem[2] = 0xd28008a0;  // MOV X0, 69
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.InvalidateCacheRange(108, 4);
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 69);
+
+    jit.SetPC(100);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 69);
+}
+
+TEST_CASE("ensure fast dispatch entry is cleared even when a block does not have any patching requirements 2", "[a64]") {
+    A64TestEnv env;
+
+    A64::UserConfig conf{&env};
+    A64::Jit jit{conf};
+
+    REQUIRE(conf.HasOptimization(OptimizationFlag::FastDispatch));
+
+    env.code_mem.emplace_back(0xd2800100);  // MOV X0, 8
+    env.code_mem.emplace_back(0xd61f0000);  // BR X0
+    env.code_mem.emplace_back(0xd2800540);  // MOV X0, 42
+    env.code_mem.emplace_back(0x14000000);  // B .
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.InvalidateCacheRange(8, 4);
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    env.code_mem[2] = 0xd28008a0;  // MOV X0, 69
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 42);
+
+    jit.InvalidateCacheRange(8, 4);
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 69);
+
+    jit.SetPC(0);
+    env.ticks_left = 4;
+    jit.Run();
+    REQUIRE(jit.GetRegister(0) == 69);
+}

tests/CMakeLists.txt

@@ -20,6 +20,8 @@ endif()
 if ("A64" IN_LIST DYNARMIC_FRONTENDS)
     target_sources(dynarmic_tests PRIVATE
         A64/a64.cpp
+        A64/misaligned_page_table.cpp
+        A64/test_invalidation.cpp
         A64/testenv.h
     )
 endif()
@@ -44,7 +46,6 @@ if (DYNARMIC_TESTS_USE_UNICORN)
     if ("A64" IN_LIST DYNARMIC_FRONTENDS)
         target_sources(dynarmic_tests PRIVATE
             A64/fuzz_with_unicorn.cpp
-            A64/misaligned_page_table.cpp
             A64/verify_unicorn.cpp
             unicorn_emu/a64_unicorn.cpp
             unicorn_emu/a64_unicorn.h