AArch64 JIT backend

Enable HashLink VM on AArch64 (Apple Silicon, ARM Linux servers, etc.)
by adding a new JIT backend alongside the existing x86/x64 one.

- Rename jit.c to jit_x86.c, extract shared code into jit_common.h/jit_shared.c
- Add jit_aarch64.c/jit_aarch64_emit.c for ARM64 instruction selection and encoding
- Add jit_elf.c for GDB JIT debug interface
- Architecture-aware JIT selection in Makefile and CMakeLists.txt
- Add aarch64 support in hl.h, profile.c, hlmodule.h, module.c

Author: bmdhacks

CMakeLists.txt

@@ -20,9 +20,7 @@ include(FindPkgConfig)
 include(CTest)
 
 set(WITH_VM_DEFAULT ON)
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "arm|aarch64" AND (NOT CMAKE_OSX_ARCHITECTURES MATCHES "x86_64"))
-    set(WITH_VM_DEFAULT OFF)
-endif()
+# VM now supports x86, x86-64, and AArch64 architectures
 
 option(WITH_VM "Whether to build the Hashlink virtual machine" ${WITH_VM_DEFAULT})
 option(BUILD_SHARED_LIBS "Build using shared libraries" ON)
@@ -224,9 +222,24 @@ else()
 endif()
 
 if (WITH_VM)
+    # Select JIT backend based on architecture
+    if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64")
+        set(JIT_SOURCES
+            src/jit_aarch64.c
+            src/jit_aarch64_emit.c
+            src/jit_elf.c
+            src/jit_shared.c
+        )
+    else()
+        set(JIT_SOURCES
+            src/jit_x86.c
+            src/jit_shared.c
+        )
+    endif()
+
     add_executable(hl
         src/code.c
-        src/jit.c
+        ${JIT_SOURCES}
         src/main.c
         src/module.c
         src/debugger.c
@@ -246,6 +259,8 @@ if (WITH_VM)
 
     if (WIN32)
         target_link_libraries(hl user32)
+    else()
+        target_link_libraries(hl dl)  # For dlopen/dlsym in jit_elf.c
     endif()
 endif()
 

Makefile

@@ -44,7 +44,16 @@ STD = src/std/array.o src/std/buffer.o src/std/bytes.o src/std/cast.o src/std/da
 	src/std/socket.o src/std/string.o src/std/sys.o src/std/types.o src/std/ucs2.o src/std/thread.o src/std/process.o \
 	src/std/track.o
 
-HL = src/code.o src/jit.o src/main.o src/module.o src/debugger.o src/profile.o
+# Conditional JIT backend selection based on architecture
+ifeq ($(ARCH),aarch64)
+    HL_JIT = src/jit_aarch64.o src/jit_aarch64_emit.o src/jit_elf.o src/jit_shared.o
+else ifeq ($(ARCH),arm64)
+    HL_JIT = src/jit_aarch64.o src/jit_aarch64_emit.o src/jit_elf.o src/jit_shared.o
+else
+    HL_JIT = src/jit_x86.o src/jit_elf.o src/jit_shared.o
+endif
+
+HL = src/code.o $(HL_JIT) src/main.o src/module.o src/debugger.o src/profile.o
 
 FMT_INCLUDE = -I include/mikktspace -I include/minimp3
 
@@ -200,8 +209,12 @@ LHL_LINK_FLAGS += -install_name @rpath/libhl.dylib
 else
 
 # Linux
-CFLAGS += -m$(MARCH) -fPIC -pthread -fno-omit-frame-pointer $(shell pkg-config --cflags sdl2)
-LFLAGS += -lm -Wl,-rpath,.:'$$ORIGIN':$(INSTALL_LIB_DIR) -Wl,--no-undefined
+# -m32/-m64 is x86-specific; skip on aarch64
+ifneq ($(ARCH),aarch64)
+CFLAGS += -m$(MARCH)
+endif
+CFLAGS += -fPIC -pthread -fno-omit-frame-pointer $(shell pkg-config --cflags sdl2)
+LFLAGS += -lm -Wl,-rpath,.:'$$ORIGIN':$(INSTALL_LIB_DIR) -Wl,--export-dynamic -Wl,--no-undefined
 
 ifeq ($(MARCH),32)
 CFLAGS += -I /usr/include/i386-linux-gnu -msse2 -mfpmath=sse
@@ -226,19 +239,12 @@ ifdef DEBUG
 CFLAGS += -g
 endif
 
-all: libhl libs
-ifeq ($(ARCH),arm64)
-	$(warning HashLink vm is not supported on arm64, skipping)
-else
-all: hl
-endif
+all: libhl libs hl
 
 install:
 	$(UNAME)==Darwin && ${MAKE} uninstall
-ifneq ($(ARCH),arm64)
 	mkdir -p $(INSTALL_BIN_DIR)
 	cp hl $(INSTALL_BIN_DIR)
-endif
 	mkdir -p $(INSTALL_LIB_DIR)
 	cp *.hdll $(INSTALL_LIB_DIR)
 	cp libhl.${LIBEXT} $(INSTALL_LIB_DIR)
@@ -258,7 +264,7 @@ src/std/regexp.o: src/std/regexp.c
 	${CC} ${CFLAGS} -o $@ -c $< ${PCRE_FLAGS}
 
 libhl: ${LIB}
-	${CC} ${CFLAGS} -o libhl.$(LIBEXT) -m${MARCH} ${LIBFLAGS} ${LHL_LINK_FLAGS} -shared $^ ${LIBHL_LDLIBS}
+	${CC} ${CFLAGS} -o libhl.$(LIBEXT) ${LIBFLAGS} ${LHL_LINK_FLAGS} -shared $^ ${LIBHL_LDLIBS}
 
 hlc: ${BOOT}
 	${CC} ${CFLAGS} -o hlc ${BOOT} ${LFLAGS} ${EXTRA_LFLAGS} ${HLC_LDLIBS}

src/hl.h

@@ -93,10 +93,14 @@
 #	define HL_BSD
 #endif
 
-#if defined(_64BITS) || defined(__x86_64__) || defined(_M_X64) || defined(__LP64__) || defined(__wasm64__)
+#if defined(_64BITS) || defined(__x86_64__) || defined(_M_X64) || defined(__LP64__) || defined(__wasm64__) || defined(__aarch64__)
 #	define HL_64
 #endif
 
+#if defined(__aarch64__) || defined(_M_ARM64)
+#	define HL_ARM64
+#endif
+
 #if defined(__GNUC__)
 #	define HL_GCC
 #endif
@@ -880,6 +884,8 @@ typedef struct {
 	int length;
 } vstring;
 
+HL_API int hl_str_cmp( vstring *a, vstring *b );
+
 #define DEFINE_PRIM(t,name,args)						DEFINE_PRIM_WITH_NAME(t,name,args,name)
 #define _DEFINE_PRIM_WITH_NAME(t,name,args,realName)	C_FUNCTION_BEGIN EXPORT void *hlp_##realName( const char **sign ) { *sign = _FUN(t,args); return (void*)(&HL_NAME(name)); } C_FUNCTION_END
 

src/hlmodule.h

@@ -115,6 +115,8 @@ typedef struct {
 	int *functions_indexes;
 } hl_code_hash;
 
+struct jit_code_entry;  /* Forward declaration for GDB JIT interface */
+
 typedef struct {
 	hl_code *code;
 	int codesize;
@@ -127,6 +129,7 @@ typedef struct {
 	hl_code_hash *hash;
 	hl_debug_infos *jit_debug;
 	jit_ctx *jit_ctx;
+	struct jit_code_entry *gdb_jit_entry;  /* GDB JIT interface registration (or NULL) */
 	hl_module_context ctx;
 } hl_module;