/* * Stack-less Just-In-Time compiler * * Copyright 2009-2012 Zoltan Herczeg (hzmester@freemail.hu). All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, are * permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this list of * conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, this list * of conditions and the following disclaimer in the documentation and/or other materials * provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef _SLJIT_LIR_H_ #define _SLJIT_LIR_H_ /* ------------------------------------------------------------------------ Stack-Less JIT compiler for multiple architectures (x86, ARM, PowerPC) ------------------------------------------------------------------------ Short description Advantages: - The execution can be continued from any LIR instruction In other words, jump into and out of the code is safe - Both target of (conditional) jump and call instructions and constants can be dynamically modified during runtime - although it is not suggested to do it frequently - very effective to cache an important value once - A fixed stack space can be allocated for local variables - The compiler is thread-safe Disadvantages: - Limited number of registers (only 6+4 integer registers, max 3+2 temporary and max 3+2 general, and 4 floating point registers) In practice: - This approach is very effective for interpreters - One of the general registers typically points to a stack interface - It can jump to any exception handler anytime (even for another function. It is safe for SLJIT.) - Fast paths can be modified during runtime reflecting the changes of the fastest execution path of the dynamic language - SLJIT supports complex memory addressing modes - mainly position independent code - Optimizations (perhaps later) - Only for basic blocks (when no labels inserted between LIR instructions) For valgrind users: - pass --smc-check=all argument to valgrind, since JIT is a "self-modifying code" */ #if !(defined SLJIT_NO_DEFAULT_CONFIG && SLJIT_NO_DEFAULT_CONFIG) #include "sljitConfig.h" #endif #include "sljitConfigInternal.h" /* --------------------------------------------------------------------- */ /* Error codes */ /* --------------------------------------------------------------------- */ /* Indicates no error. */ #define SLJIT_SUCCESS 0 /* After the call of sljit_generate_code(), the error code of the compiler is set to this value to avoid future sljit calls (in debug mode at least). The complier should be freed after sljit_generate_code(). */ #define SLJIT_ERR_COMPILED 1 /* Cannot allocate non executable memory. */ #define SLJIT_ERR_ALLOC_FAILED 2 /* Cannot allocate executable memory. Only for sljit_generate_code() */ #define SLJIT_ERR_EX_ALLOC_FAILED 3 /* return value for SLJIT_CONFIG_UNSUPPORTED empty architecture. */ #define SLJIT_ERR_UNSUPPORTED 4 /* --------------------------------------------------------------------- */ /* Registers */ /* --------------------------------------------------------------------- */ #define SLJIT_UNUSED 0 /* Temporary (scratch) registers may not preserve their values across function calls. */ #define SLJIT_TEMPORARY_REG1 1 #define SLJIT_TEMPORARY_REG2 2 #define SLJIT_TEMPORARY_REG3 3 /* Note: Extra Registers cannot be used for memory addressing. */ /* Note: on x86-32, these registers are emulated (using stack loads & stores). */ #define SLJIT_TEMPORARY_EREG1 4 #define SLJIT_TEMPORARY_EREG2 5 /* General (saved) registers preserve their values across function calls. */ #define SLJIT_GENERAL_REG1 6 #define SLJIT_GENERAL_REG2 7 #define SLJIT_GENERAL_REG3 8 /* Note: Extra Registers cannot be used for memory addressing. */ /* Note: on x86-32, these registers are emulated (using stack loads & stores). */ #define SLJIT_GENERAL_EREG1 9 #define SLJIT_GENERAL_EREG2 10 /* Read-only register (cannot be the destination of an operation). */ /* Note: SLJIT_MEM2( ... , SLJIT_LOCALS_REG) is not supported (x86 limitation). */ /* Note: SLJIT_LOCALS_REG is not necessary the real stack pointer. See sljit_emit_enter. */ #define SLJIT_LOCALS_REG 11 /* Number of registers. */ #define SLJIT_NO_TMP_REGISTERS 5 #define SLJIT_NO_GEN_REGISTERS 5 #define SLJIT_NO_REGISTERS 11 /* Return with machine word. */ #define SLJIT_RETURN_REG SLJIT_TEMPORARY_REG1 /* x86 prefers temporary registers for special purposes. If other registers are used such purpose, it costs a little performance drawback. It doesn't matter for other archs. */ #define SLJIT_PREF_SHIFT_REG SLJIT_TEMPORARY_REG3 /* --------------------------------------------------------------------- */ /* Floating point registers */ /* --------------------------------------------------------------------- */ /* Note: SLJIT_UNUSED as destination is not valid for floating point operations, since they cannot be used for setting flags. */ /* Floating point operations are performed on double precision values. */ #define SLJIT_FLOAT_REG1 1 #define SLJIT_FLOAT_REG2 2 #define SLJIT_FLOAT_REG3 3 #define SLJIT_FLOAT_REG4 4 /* --------------------------------------------------------------------- */ /* Main structures and functions */ /* --------------------------------------------------------------------- */ struct sljit_memory_fragment { struct sljit_memory_fragment *next; sljit_uw used_size; sljit_ub memory[1]; }; struct sljit_label { struct sljit_label *next; sljit_uw addr; /* The maximum size difference. */ sljit_uw size; }; struct sljit_jump { struct sljit_jump *next; sljit_uw addr; sljit_w flags; union { sljit_uw target; struct sljit_label* label; } u; }; struct sljit_const { struct sljit_const *next; sljit_uw addr; }; struct sljit_compiler { int error; struct sljit_label *labels; struct sljit_jump *jumps; struct sljit_const *consts; struct sljit_label *last_label; struct sljit_jump *last_jump; struct sljit_const *last_const; struct sljit_memory_fragment *buf; struct sljit_memory_fragment *abuf; /* Used local registers. */ int temporaries; /* Used general registers. */ int generals; /* Local stack size. */ int local_size; /* Code size. */ sljit_uw size; /* For statistical purposes. */ sljit_uw executable_size; #if (defined SLJIT_CONFIG_X86_32 && SLJIT_CONFIG_X86_32) int args; int temporaries_start; int generals_start; #endif #if (defined SLJIT_CONFIG_X86_64 && SLJIT_CONFIG_X86_64) int mode32; #ifdef _WIN64 int has_locals; #endif #endif #if (defined SLJIT_CONFIG_X86_32 && SLJIT_CONFIG_X86_32) || (defined SLJIT_CONFIG_X86_64 && SLJIT_CONFIG_X86_64) int flags_saved; #endif #if (defined SLJIT_CONFIG_ARM_V5 && SLJIT_CONFIG_ARM_V5) /* Constant pool handling. */ sljit_uw *cpool; sljit_ub *cpool_unique; sljit_uw cpool_diff; sljit_uw cpool_fill; /* General fields. */ /* Contains pointer, "ldr pc, [...]" pairs. */ sljit_uw patches; #endif #if (defined SLJIT_CONFIG_ARM_V5 && SLJIT_CONFIG_ARM_V5) || (defined SLJIT_CONFIG_ARM_V7 && SLJIT_CONFIG_ARM_V7) /* Temporary fields. */ sljit_uw shift_imm; int cache_arg; sljit_w cache_argw; #endif #if (defined SLJIT_CONFIG_ARM_THUMB2 && SLJIT_CONFIG_ARM_THUMB2) int cache_arg; sljit_w cache_argw; #endif #if (defined SLJIT_CONFIG_PPC_32 && SLJIT_CONFIG_PPC_32) || (defined SLJIT_CONFIG_PPC_64 && SLJIT_CONFIG_PPC_64) int has_locals; sljit_w imm; int cache_arg; sljit_w cache_argw; #endif #if (defined SLJIT_CONFIG_MIPS_32 && SLJIT_CONFIG_MIPS_32) int has_locals; int delay_slot; int cache_arg; sljit_w cache_argw; #endif #if (defined SLJIT_VERBOSE && SLJIT_VERBOSE) FILE* verbose; #endif #if (defined SLJIT_VERBOSE && SLJIT_VERBOSE) || (defined SLJIT_DEBUG && SLJIT_DEBUG) int skip_checks; #endif }; /* --------------------------------------------------------------------- */ /* Main functions */ /* --------------------------------------------------------------------- */ /* Creates an sljit compiler. Returns NULL if failed. */ SLJIT_API_FUNC_ATTRIBUTE struct sljit_compiler* sljit_create_compiler(void); /* Free everything except the codes. */ SLJIT_API_FUNC_ATTRIBUTE void sljit_free_compiler(struct sljit_compiler *compiler); static SLJIT_INLINE int sljit_get_compiler_error(struct sljit_compiler *compiler) { return compiler->error; } /* Allocate a small amount of memory. The size must be <= 64 bytes on 32 bit, and <= 128 bytes on 64 bit architectures. The memory area is owned by the compiler, and freed by sljit_free_compiler. The returned pointer is sizeof(sljit_w) aligned. Excellent for allocating small blocks during the compiling, and no need to worry about freeing them. The size is enough to contain at most 16 pointers. If the size is outside of the range, the function will return with NULL, but this return value does not indicate that there is no more memory (does not set the compiler to out-of-memory status). */ SLJIT_API_FUNC_ATTRIBUTE void* sljit_alloc_memory(struct sljit_compiler *compiler, int size); #if (defined SLJIT_VERBOSE && SLJIT_VERBOSE) /* Passing NULL disables verbose. */ SLJIT_API_FUNC_ATTRIBUTE void sljit_compiler_verbose(struct sljit_compiler *compiler, FILE* verbose); #endif SLJIT_API_FUNC_ATTRIBUTE void* sljit_generate_code(struct sljit_compiler *compiler); SLJIT_API_FUNC_ATTRIBUTE void sljit_free_code(void* code); /* After the code generation we can retrieve the allocated executable memory size, although this area may not be fully filled with instructions depending on some optimizations. This function is useful only for statistical purposes. Before a successful code generation, this function returns with 0. */ static SLJIT_INLINE sljit_uw sljit_get_generated_code_size(struct sljit_compiler *compiler) { return compiler->executable_size; } /* Instruction generation. Returns with error code. */ /* Entry instruction. The instruction has "args" number of arguments and will use the first "general" number of general registers. The arguments are passed into the general registers (arg1 to general_reg1, and so on). Thus, "args" must be less or equal than "general". A local_size extra stack space is allocated for the jit code (must be less or equal than SLJIT_MAX_LOCAL_SIZE), which can accessed through SLJIT_LOCALS_REG (see the notes there). SLJIT_LOCALS_REG is not necessary the real stack pointer! It just points somewhere in the stack if local_size > 0 (!). Thus, the only thing which is known that the memory area between SLJIT_LOCALS_REG and SLJIT_LOCALS_REG + local_size is a valid stack area if local_size > 0 */ /* Note: multiple calls of this function overwrites the previous call. */ #define SLJIT_MAX_LOCAL_SIZE 65536 SLJIT_API_FUNC_ATTRIBUTE int sljit_emit_enter(struct sljit_compiler *compiler, int args, int temporaries, int generals, int local_size); /* Since sljit_emit_return (and many asserts) uses variables which are initialized by sljit_emit_enter, a simple return is not possible if these variables are not initialized. sljit_fake_enter does not emit any instruction, just initialize those variables. */ /* Note: multiple calls of this function overwrites the previous call. */ SLJIT_API_FUNC_ATTRIBUTE void sljit_fake_enter(struct sljit_compiler *compiler, int args, int temporaries, int generals, int local_size); /* Return from jit. See below the possible values for src and srcw. */ SLJIT_API_FUNC_ATTRIBUTE int sljit_emit_return(struct sljit_compiler *compiler, int src, sljit_w srcw); /* Really fast calling method for utility functions inside sljit (see SLJIT_FAST_CALL). All registers and even the stack frame is passed to the callee. The return address is preserved in dst/dstw by sljit_emit_fast_enter, and sljit_emit_fast_return can use this as a return value later. */ /* Note: only for sljit specific, non ABI compilant calls. Fast, since only a few machine instructions are needed. Excellent for small uility functions, where saving general registers and setting up a new stack frame would cost too much performance. However, it is still possible to return to the address of the caller (or anywhere else). */ /* Note: flags are not changed (unlike sljit_emit_enter / sljit_emit_return). */ /* Note: although sljit_emit_fast_return could be replaced by an ijump, it is not suggested, since many architectures do clever branch prediction on call / return instruction pairs. */ SLJIT_API_FUNC_ATTRIBUTE int sljit_emit_fast_enter(struct sljit_compiler *compiler, int dst, sljit_w dstw, int args, int temporaries, int generals, int local_size); SLJIT_API_FUNC_ATTRIBUTE int sljit_emit_fast_return(struct sljit_compiler *compiler, int src, sljit_w srcw); /* Source and destination values for arithmetical instructions imm - a simple immediate value (cannot be used as a destination) reg - any of the registers (immediate argument must be 0) [imm] - absolute immediate memory address [reg+imm] - indirect memory address [reg+(reg<addr; } static SLJIT_INLINE sljit_uw sljit_get_jump_addr(struct sljit_jump *jump) { return jump->addr; } static SLJIT_INLINE sljit_uw sljit_get_const_addr(struct sljit_const *const_) { return const_->addr; } /* Only the address is required to rewrite the code. */ SLJIT_API_FUNC_ATTRIBUTE void sljit_set_jump_addr(sljit_uw addr, sljit_uw new_addr); SLJIT_API_FUNC_ATTRIBUTE void sljit_set_const(sljit_uw addr, sljit_w new_constant); /* --------------------------------------------------------------------- */ /* Miscellaneous utility functions */ /* --------------------------------------------------------------------- */ #define SLJIT_MAJOR_VERSION 0 #define SLJIT_MINOR_VERSION 82 /* Get the human readable name of the platfrom. Can be useful for debugging on platforms like ARM, where ARM and Thumb2 functions can be mixed. */ SLJIT_API_FUNC_ATTRIBUTE SLJIT_CONST char* sljit_get_platform_name(void); /* Portble helper function to get an offset of a member. */ #define SLJIT_OFFSETOF(base, member) ((sljit_w)(&((base*)0x10)->member) - 0x10) #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK) /* This global lock is useful to compile common functions. */ SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_grab_lock(void); SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_release_lock(void); #endif #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) /* The sljit_stack is a utiliy feature of sljit, which allocates a writable memory region between base (inclusive) and limit (exclusive). Both base and limit is a pointer, and base is always <= than limit. This feature uses the "address space reserve" feature of modern operating systems. Basically we don't need to allocate a huge memory block in one step for the worst case, we can start with a smaller chunk and extend it later. Since the address space is reserved, the data never copied to other regions, thus it is safe to store pointers here. */ /* Note: The base field is aligned to PAGE_SIZE bytes (usually 4k or more). Note: stack growing should not happen in small steps: 4k, 16k or even bigger growth is better. Note: this structure may not be supported by all operating systems. Some kind of fallback mechanism is suggested when SLJIT_UTIL_STACK is not defined. */ struct sljit_stack { /* User data, anything can be stored here. Starting with the same value as base. */ sljit_uw top; /* These members are read only. */ sljit_uw base; sljit_uw limit; sljit_uw max_limit; }; /* Returns NULL if unsuccessful. Note: limit and max_limit contains the size for stack allocation Note: the top field is initialized to base. */ SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_CALL sljit_allocate_stack(sljit_uw limit, sljit_uw max_limit); SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_free_stack(struct sljit_stack* stack); /* Can be used to increase (allocate) or decrease (free) the memory area. Returns with a non-zero value if unsuccessful. If new_limit is greater than max_limit, it will fail. It is very easy to implement a stack data structure, since the growth ratio can be added to the current limit, and sljit_stack_resize will do all the necessary checks. The fields of the stack are not changed if sljit_stack_resize fails. */ SLJIT_API_FUNC_ATTRIBUTE sljit_w SLJIT_CALL sljit_stack_resize(struct sljit_stack* stack, sljit_uw new_limit); #endif /* (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) */ #if !(defined SLJIT_INDIRECT_CALL && SLJIT_INDIRECT_CALL) /* Get the entry address of a given function. */ #define SLJIT_FUNC_OFFSET(func_name) ((sljit_w)func_name) #else /* !(defined SLJIT_INDIRECT_CALL && SLJIT_INDIRECT_CALL) */ /* All JIT related code should be placed in the same context (library, binary, etc.). */ #define SLJIT_FUNC_OFFSET(func_name) ((sljit_w)*(void**)func_name) /* For powerpc64, the function pointers point to a context descriptor. */ struct sljit_function_context { sljit_w addr; sljit_w r2; sljit_w r11; }; /* Fill the context arguments using the addr and the function. If func_ptr is NULL, it will not be set to the address of context If addr is NULL, the function address also comes from the func pointer. */ SLJIT_API_FUNC_ATTRIBUTE void sljit_set_function_context(void** func_ptr, struct sljit_function_context* context, sljit_w addr, void* func); #endif /* !(defined SLJIT_INDIRECT_CALL && SLJIT_INDIRECT_CALL) */ #endif /* _SLJIT_LIR_H_ */