From 69f2baec414a9cab64b19735fd40e34504c5a160 Mon Sep 17 00:00:00 2001
From: SChernykh <sergey.v.chernykh@gmail.com>
Date: Wed, 8 Sep 2021 14:54:55 +0200
Subject: [PATCH] Fixed code cache flushing on macOS

---
 CMakeLists.txt           |  6 ++++++
 src/jit_compiler_a64.cpp | 16 ++++------------
 src/virtual_memory.cpp   | 14 ++++++++++++++
 src/virtual_memory.hpp   |  1 +
 4 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 89b23c2..00f82fe 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -112,6 +112,7 @@ endif()
 
 include(CheckCXXCompilerFlag)
 include(CheckCCompilerFlag)
+include(CheckSymbolExists)
 
 function(add_flag flag)
   string(REPLACE "-" "_" supported_cxx ${flag}_cxx)
@@ -216,6 +217,11 @@ if(ARM_ID STREQUAL "aarch64" OR ARM_ID STREQUAL "arm64" OR ARM_ID STREQUAL "armv
   endif()
 endif()
 
+check_symbol_exists("__builtin___clear_cache" "stdlib.h" HAVE_BUILTIN_CLEAR_CACHE)
+if (HAVE_BUILTIN_CLEAR_CACHE)
+  add_definitions(-DHAVE_BUILTIN_CLEAR_CACHE)
+endif()
+
 set(RANDOMX_INCLUDE "${CMAKE_CURRENT_SOURCE_DIR}/src" CACHE STRING "RandomX Include path")
 
 add_library(randomx ${randomx_sources})
diff --git a/src/jit_compiler_a64.cpp b/src/jit_compiler_a64.cpp
index e45774e..35a1b7b 100644
--- a/src/jit_compiler_a64.cpp
+++ b/src/jit_compiler_a64.cpp
@@ -96,9 +96,7 @@ JitCompilerA64::JitCompilerA64()
 	memset(reg_changed_offset, 0, sizeof(reg_changed_offset));
 	memcpy(code, (void*) randomx_program_aarch64, CodeSize);
 
-#ifdef __GNUC__
-	__builtin___clear_cache(reinterpret_cast<char*>(code), reinterpret_cast<char*>(code + CodeSize));
-#endif
+	flushInstructionCache(code, code + CodeSize);
 }
 
 JitCompilerA64::~JitCompilerA64()
@@ -167,9 +165,7 @@ void JitCompilerA64::generateProgram(Program& program, ProgramConfiguration& con
 	codePos = ((uint8_t*)randomx_program_aarch64_update_spMix1) - ((uint8_t*)randomx_program_aarch64);
 	emit32(ARMV8A::EOR | 10 | (IntRegMap[config.readReg0] << 5) | (IntRegMap[config.readReg1] << 16), code, codePos);
 
-#ifdef __GNUC__
-	__builtin___clear_cache(reinterpret_cast<char*>(code + MainLoopBegin), reinterpret_cast<char*>(code + codePos));
-#endif
+	flushInstructionCache(code + MainLoopBegin, code + codePos);
 }
 
 void JitCompilerA64::generateProgramLight(Program& program, ProgramConfiguration& config, uint32_t datasetOffset)
@@ -224,9 +220,7 @@ void JitCompilerA64::generateProgramLight(Program& program, ProgramConfiguration
 	emit32(ARMV8A::ADD_IMM_LO | 2 | (2 << 5) | (imm_lo << 10), code, codePos);
 	emit32(ARMV8A::ADD_IMM_HI | 2 | (2 << 5) | (imm_hi << 10), code, codePos);
 
-#ifdef __GNUC__
-	__builtin___clear_cache(reinterpret_cast<char*>(code + MainLoopBegin), reinterpret_cast<char*>(code + codePos));
-#endif
+	flushInstructionCache(code + MainLoopBegin, code + codePos);
 }
 
 template<size_t N>
@@ -342,9 +336,7 @@ void JitCompilerA64::generateSuperscalarHash(SuperscalarProgram(&programs)[N], s
 	memcpy(code + codePos, p1, p2 - p1);
 	codePos += p2 - p1;
 
-#ifdef __GNUC__
-	__builtin___clear_cache(reinterpret_cast<char*>(code + CodeSize), reinterpret_cast<char*>(code + codePos));
-#endif
+	flushInstructionCache(code + CodeSize, code + codePos);
 }
 
 template void JitCompilerA64::generateSuperscalarHash(SuperscalarProgram(&programs)[RANDOMX_CACHE_ACCESSES], std::vector<uint64_t> &reciprocalCache);
diff --git a/src/virtual_memory.cpp b/src/virtual_memory.cpp
index 262081a..1cd7e9b 100644
--- a/src/virtual_memory.cpp
+++ b/src/virtual_memory.cpp
@@ -34,6 +34,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <windows.h>
 #else
 #ifdef __APPLE__
+#include <libkern/OSCacheControl.h>
 #include <mach/vm_statistics.h>
 #include <TargetConditionals.h>
 # if defined(__aarch64__) && TARGET_OS_OSX
@@ -195,3 +196,16 @@ void freePagedMemory(void* ptr, std::size_t bytes) {
 	munmap(ptr, bytes);
 #endif
 }
+
+void flushInstructionCache(void* begin, void* end)
+{
+	const size_t size = static_cast<size_t>(reinterpret_cast<char*>(end) - reinterpret_cast<char*>(begin));
+
+#if defined(_WIN32) || defined(__CYGWIN__)
+	::FlushInstructionCache(GetCurrentProcess(), begin, size);
+#elif defined(__APPLE__)
+	sys_icache_invalidate(begin, size);
+#elif defined(__GNUC__) || defined(HAVE_BUILTIN_CLEAR_CACHE)
+	__builtin___clear_cache(reinterpret_cast<char*>(begin), reinterpret_cast<char*>(end));
+#endif
+}
diff --git a/src/virtual_memory.hpp b/src/virtual_memory.hpp
index 9e8bc29..13dad0b 100644
--- a/src/virtual_memory.hpp
+++ b/src/virtual_memory.hpp
@@ -40,3 +40,4 @@ void setPagesRX(void*, std::size_t);
 void setPagesRWX(void*, std::size_t);
 void* allocLargePagesMemory(std::size_t);
 void freePagedMemory(void*, std::size_t);
+void flushInstructionCache(void* begin, void* end);