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Implement the segue optimization for LLVM AOT/JIT (#2230)

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Segue is an optimization technology which uses x86 segment register to store
the WebAssembly linear memory base address, so as to remove most of the cost
of SFI (Software-based Fault Isolation) base addition and free up a general
purpose register, by this way it may:
- Improve the performance of JIT/AOT
- Reduce the footprint of JIT/AOT, the JIT/AOT code generated is smaller
- Reduce the compilation time of JIT/AOT

This PR uses the x86-64 GS segment register to apply the optimization, currently
it supports linux and linux-sgx platforms on x86-64 target. By default it is disabled,
developer can use the option below to enable it for wamrc and iwasm(with LLVM
JIT enabled):
```bash
wamrc --enable-segue=[<flags>] -o output_file wasm_file
iwasm --enable-segue=[<flags>] wasm_file [args...]
```
`flags` can be:
    i32.load, i64.load, f32.load, f64.load, v128.load,
    i32.store, i64.store, f32.store, f64.store, v128.store
Use comma to separate them, e.g. `--enable-segue=i32.load,i64.store`,
and `--enable-segue` means all flags are added.

Acknowledgement:
Many thanks to Intel Labs, UC San Diego and UT Austin teams for introducing this
technology and the great support and guidance!

Signed-off-by: Wenyong Huang <wenyong.huang@intel.com>
Co-authored-by: Vahldiek-oberwagner, Anjo Lucas <anjo.lucas.vahldiek-oberwagner@intel.com>
This commit is contained in:
Wenyong Huang
2023-05-26 10:13:33 +08:00
committed by GitHub
parent 27239723a9
commit 76be848ec3
42 changed files with 1864 additions and 123 deletions
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82
product-mini/platforms/posix/main.c
View File

@ -54,6 +54,14 @@ print_help()
#if WASM_ENABLE_JIT != 0
printf(" --llvm-jit-size-level=n Set LLVM JIT size level, default is 3\n");
printf(" --llvm-jit-opt-level=n Set LLVM JIT optimization level, default is 3\n");
#if defined(os_writegsbase)
printf(" --enable-segue[=<flags>] Enable using segment register GS as the base address of\n");
printf(" linear memory, which may improve performance, flags can be:\n");
printf(" i32.load, i64.load, f32.load, f64.load, v128.load,\n");
printf(" i32.store, i64.store, f32.store, f64.store, v128.store\n");
printf(" Use comma to separate, e.g. --enable-segue=i32.load,i64.store\n");
printf(" and --enable-segue means all flags are added.\n");
#endif
#endif
printf(" --repl Start a very simple REPL (read-eval-print-loop) mode\n"
" that runs commands in the form of \"FUNC ARG...\"\n");
@ -117,13 +125,13 @@ app_instance_func(wasm_module_inst_t module_inst, const char *func_name)
}
/**
* Split a space separated strings into an array of strings
* Split a string into an array of strings
* Returns NULL on failure
* Memory must be freed by caller
* Based on: http://stackoverflow.com/a/11198630/471795
*/
static char **
split_string(char *str, int *count)
split_string(char *str, int *count, const char *delimer)
{
char **res = NULL, **res1;
char *p;
@ -131,7 +139,7 @@ split_string(char *str, int *count)
/* split string and append tokens to 'res' */
do {
p = strtok(str, " ");
p = strtok(str, delimer);
str = NULL;
res1 = res;
res = (char **)realloc(res1, sizeof(char *) * (uint32)(idx + 1));
@ -180,7 +188,7 @@ app_instance_repl(wasm_module_inst_t module_inst)
printf("exit repl mode\n");
break;
}
app_argv = split_string(cmd, &app_argc);
app_argv = split_string(cmd, &app_argc, " ");
if (app_argv == NULL) {
LOG_ERROR("Wasm prepare param failed: split string failed.\n");
break;
@ -195,6 +203,59 @@ app_instance_repl(wasm_module_inst_t module_inst)
return NULL;
}
#if WASM_ENABLE_JIT != 0
static uint32
resolve_segue_flags(char *str_flags)
{
uint32 segue_flags = 0;
int32 flag_count, i;
char **flag_list;
flag_list = split_string(str_flags, &flag_count, ",");
if (flag_list) {
for (i = 0; i < flag_count; i++) {
if (!strcmp(flag_list[i], "i32.load")) {
segue_flags |= 1 << 0;
}
else if (!strcmp(flag_list[i], "i64.load")) {
segue_flags |= 1 << 1;
}
else if (!strcmp(flag_list[i], "f32.load")) {
segue_flags |= 1 << 2;
}
else if (!strcmp(flag_list[i], "f64.load")) {
segue_flags |= 1 << 3;
}
else if (!strcmp(flag_list[i], "v128.load")) {
segue_flags |= 1 << 4;
}
else if (!strcmp(flag_list[i], "i32.store")) {
segue_flags |= 1 << 8;
}
else if (!strcmp(flag_list[i], "i64.store")) {
segue_flags |= 1 << 9;
}
else if (!strcmp(flag_list[i], "f32.store")) {
segue_flags |= 1 << 10;
}
else if (!strcmp(flag_list[i], "f64.store")) {
segue_flags |= 1 << 11;
}
else if (!strcmp(flag_list[i], "v128.store")) {
segue_flags |= 1 << 12;
}
else {
/* invalid flag */
segue_flags = (uint32)-1;
break;
}
}
free(flag_list);
}
return segue_flags;
}
#endif /* end of WASM_ENABLE_JIT != 0 */
#if WASM_ENABLE_LIBC_WASI != 0
static bool
validate_env_str(char *env)
@ -367,6 +428,7 @@ main(int argc, char *argv[])
#if WASM_ENABLE_JIT != 0
uint32 llvm_jit_size_level = 3;
uint32 llvm_jit_opt_level = 3;
uint32 segue_flags = 0;
#endif
wasm_module_t wasm_module = NULL;
wasm_module_inst_t wasm_module_inst = NULL;
@ -487,7 +549,16 @@ main(int argc, char *argv[])
llvm_jit_opt_level = 3;
}
}
#endif
else if (!strcmp(argv[0], "--enable-segue")) {
/* all flags are enabled */
segue_flags = 0x1F1F;
}
else if (!strncmp(argv[0], "--enable-segue=", 15)) {
segue_flags = resolve_segue_flags(argv[0] + 15);
if (segue_flags == (uint32)-1)
return print_help();
}
#endif /* end of WASM_ENABLE_JIT != 0 */
#if WASM_ENABLE_LIBC_WASI != 0
else if (!strncmp(argv[0], "--dir=", 6)) {
if (argv[0][6] == '\0')
@ -632,6 +703,7 @@ main(int argc, char *argv[])
#if WASM_ENABLE_JIT != 0
init_args.llvm_jit_size_level = llvm_jit_size_level;
init_args.llvm_jit_opt_level = llvm_jit_opt_level;
init_args.segue_flags = segue_flags;
#endif
#if WASM_ENABLE_DEBUG_INTERP != 0