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Merged
merged 10 commits into from
May 27, 2022
Merged

Remove custom alloca #8513

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a34e543
Remove custom alloca
Girgias May 7, 2022
1af023e
Drop new windows specific code
Girgias May 8, 2022
a4fa962
Use different alloca flags for crypt_sha
Girgias May 8, 2022
a1ef3e4
Use arena in DCE
Girgias May 8, 2022
e460cd3
Drop memset
Girgias May 8, 2022
6edd254
Reinstate memset to -1
Girgias May 8, 2022
88c668b
Use seperate use heap variables from s and p byte sequences
Girgias May 8, 2022
ead0565
Use ZEND_MM in debug mode instead of alloca
Girgias May 11, 2022
2d77320
Group alloca handling together
Girgias May 11, 2022
d841906
Set ALLOCA flag in crypt_sha files
Girgias May 11, 2022
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19 changes: 9 additions & 10 deletions Zend/Optimizer/dce.c
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Expand Up @@ -523,7 +523,7 @@ static inline bool may_throw_dce_exception(const zend_op *opline) {
return opline->opcode == ZEND_ADD_ARRAY_ELEMENT && opline->op2_type == IS_UNUSED;
}

int dce_optimize_op_array(zend_op_array *op_array, zend_ssa *ssa, bool reorder_dtor_effects) {
int dce_optimize_op_array(zend_op_array *op_array, zend_optimizer_ctx *optimizer_ctx, zend_ssa *ssa, bool reorder_dtor_effects) {
int i;
zend_ssa_phi *phi;
int removed_ops = 0;
Expand All @@ -536,20 +536,17 @@ int dce_optimize_op_array(zend_op_array *op_array, zend_ssa *ssa, bool reorder_d
ctx.op_array = op_array;
ctx.reorder_dtor_effects = reorder_dtor_effects;

void *checkpoint = zend_arena_checkpoint(optimizer_ctx->arena);
/* We have no dedicated phi vector, so we use the whole ssa var vector instead */
ctx.instr_worklist_len = zend_bitset_len(op_array->last);
ctx.instr_worklist = alloca(sizeof(zend_ulong) * ctx.instr_worklist_len);
memset(ctx.instr_worklist, 0, sizeof(zend_ulong) * ctx.instr_worklist_len);
ctx.instr_worklist = zend_arena_calloc(&optimizer_ctx->arena, ctx.instr_worklist_len, sizeof(zend_ulong));
ctx.phi_worklist_len = zend_bitset_len(ssa->vars_count);
ctx.phi_worklist = alloca(sizeof(zend_ulong) * ctx.phi_worklist_len);
memset(ctx.phi_worklist, 0, sizeof(zend_ulong) * ctx.phi_worklist_len);
ctx.phi_worklist_no_val = alloca(sizeof(zend_ulong) * ctx.phi_worklist_len);
memset(ctx.phi_worklist_no_val, 0, sizeof(zend_ulong) * ctx.phi_worklist_len);
ctx.phi_worklist = zend_arena_calloc(&optimizer_ctx->arena, ctx.phi_worklist_len, sizeof(zend_ulong));
ctx.phi_worklist_no_val = zend_arena_calloc(&optimizer_ctx->arena, ctx.phi_worklist_len, sizeof(zend_ulong));

/* Optimistically assume all instructions and phis to be dead */
ctx.instr_dead = alloca(sizeof(zend_ulong) * ctx.instr_worklist_len);
memset(ctx.instr_dead, 0, sizeof(zend_ulong) * ctx.instr_worklist_len);
ctx.phi_dead = alloca(sizeof(zend_ulong) * ctx.phi_worklist_len);
ctx.instr_dead = zend_arena_calloc(&optimizer_ctx->arena, ctx.instr_worklist_len, sizeof(zend_ulong));
ctx.phi_dead = zend_arena_alloc(&optimizer_ctx->arena, ctx.phi_worklist_len * sizeof(zend_ulong));
memset(ctx.phi_dead, 0xff, sizeof(zend_ulong) * ctx.phi_worklist_len);

/* Mark non-CV phis as live. Even if the result is unused, we generally cannot remove one
Expand Down Expand Up @@ -664,5 +661,7 @@ int dce_optimize_op_array(zend_op_array *op_array, zend_ssa *ssa, bool reorder_d
}
} FOREACH_PHI_END();

zend_arena_release(&optimizer_ctx->arena, checkpoint);

return removed_ops;
}
2 changes: 1 addition & 1 deletion Zend/Optimizer/dfa_pass.c
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Expand Up @@ -1076,7 +1076,7 @@ void zend_dfa_optimize_op_array(zend_op_array *op_array, zend_optimizer_ctx *ctx
}

if (ZEND_OPTIMIZER_PASS_14 & ctx->optimization_level) {
if (dce_optimize_op_array(op_array, ssa, 0)) {
if (dce_optimize_op_array(op_array, ctx, ssa, 0)) {
remove_nops = 1;
}
if (zend_dfa_optimize_jmps(op_array, ssa)) {
Expand Down
2 changes: 1 addition & 1 deletion Zend/Optimizer/zend_optimizer_internal.h
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Expand Up @@ -121,7 +121,7 @@ uint32_t zend_optimizer_classify_function(zend_string *name, uint32_t num_args);
void zend_optimizer_migrate_jump(zend_op_array *op_array, zend_op *new_opline, zend_op *opline);
void zend_optimizer_shift_jump(zend_op_array *op_array, zend_op *opline, uint32_t *shiftlist);
int sccp_optimize_op_array(zend_optimizer_ctx *ctx, zend_op_array *op_array, zend_ssa *ssa, zend_call_info **call_map);
int dce_optimize_op_array(zend_op_array *op_array, zend_ssa *ssa, bool reorder_dtor_effects);
int dce_optimize_op_array(zend_op_array *op_array, zend_optimizer_ctx *optimizer_ctx, zend_ssa *ssa, bool reorder_dtor_effects);
zend_result zend_ssa_escape_analysis(const zend_script *script, zend_op_array *op_array, zend_ssa *ssa);

typedef void (*zend_op_array_func_t)(zend_op_array *, void *context);
Expand Down
45 changes: 22 additions & 23 deletions Zend/zend_portability.h
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Original file line number Diff line number Diff line change
Expand Up @@ -63,10 +63,6 @@

#include <limits.h>

#if HAVE_ALLOCA_H && !defined(_ALLOCA_H)
# include <alloca.h>
#endif

#if defined(ZEND_WIN32) && !defined(__clang__)
#include <intrin.h>
#endif
Expand Down Expand Up @@ -181,6 +177,9 @@
# define ZEND_EXTENSIONS_SUPPORT 0
#endif

#if defined(HAVE_ALLOCA_H) && !defined(_ALLOCA_H)
# include <alloca.h>
#endif
/* AIX requires this to be the first thing in the file. */
#ifndef __GNUC__
# ifndef HAVE_ALLOCA_H
Expand All @@ -194,6 +193,25 @@ char *alloca();
# endif
#endif

#if !ZEND_DEBUG && (defined(HAVE_ALLOCA) || (defined (__GNUC__) && __GNUC__ >= 2)) && !(defined(ZTS) && defined(HPUX)) && !defined(DARWIN)
# define ZEND_ALLOCA_MAX_SIZE (32 * 1024)
# define ALLOCA_FLAG(name) \
bool name;
# define SET_ALLOCA_FLAG(name) \
name = true
# define do_alloca_ex(size, limit, use_heap) \
((use_heap = (UNEXPECTED((size) > (limit)))) ? emalloc(size) : alloca(size))
# define do_alloca(size, use_heap) \
do_alloca_ex(size, ZEND_ALLOCA_MAX_SIZE, use_heap)
# define free_alloca(p, use_heap) \
do { if (UNEXPECTED(use_heap)) efree(p); } while (0)
#else
# define ALLOCA_FLAG(name)
# define SET_ALLOCA_FLAG(name)
# define do_alloca(p, use_heap) emalloc(p)
# define free_alloca(p, use_heap) efree(p)
#endif

#if ZEND_GCC_VERSION >= 2096 || __has_attribute(__malloc__)
# define ZEND_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
#else
Expand Down Expand Up @@ -345,25 +363,6 @@ char *alloca();
# define XtOffsetOf(s_type, field) offsetof(s_type, field)
#endif

#if (defined(HAVE_ALLOCA) || (defined (__GNUC__) && __GNUC__ >= 2)) && !(defined(ZTS) && defined(HPUX)) && !defined(DARWIN)
# define ZEND_ALLOCA_MAX_SIZE (32 * 1024)
# define ALLOCA_FLAG(name) \
bool name;
# define SET_ALLOCA_FLAG(name) \
name = 1
# define do_alloca_ex(size, limit, use_heap) \
((use_heap = (UNEXPECTED((size) > (limit)))) ? emalloc(size) : alloca(size))
# define do_alloca(size, use_heap) \
do_alloca_ex(size, ZEND_ALLOCA_MAX_SIZE, use_heap)
# define free_alloca(p, use_heap) \
do { if (UNEXPECTED(use_heap)) efree(p); } while (0)
#else
# define ALLOCA_FLAG(name)
# define SET_ALLOCA_FLAG(name)
# define do_alloca(p, use_heap) emalloc(p)
# define free_alloca(p, use_heap) efree(p)
#endif

#ifdef HAVE_SIGSETJMP
# define SETJMP(a) sigsetjmp(a, 0)
# define LONGJMP(a,b) siglongjmp(a, b)
Expand Down
2 changes: 1 addition & 1 deletion configure.ac
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Original file line number Diff line number Diff line change
Expand Up @@ -1610,7 +1610,7 @@ PHP_INSTALL_HEADERS([Zend/Optimizer], [ \
PHP_ADD_SOURCES(TSRM, TSRM.c, -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1)

PHP_ADD_SOURCES(main, main.c snprintf.c spprintf.c \
fopen_wrappers.c alloca.c php_scandir.c \
fopen_wrappers.c php_scandir.c \
php_ini_builder.c \
php_ini.c SAPI.c rfc1867.c php_content_types.c strlcpy.c \
strlcat.c explicit_bzero.c reentrancy.c php_variables.c php_ticks.c \
Expand Down
30 changes: 23 additions & 7 deletions ext/standard/crypt_sha256.c
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Expand Up @@ -10,7 +10,6 @@

#ifdef PHP_WIN32
# define __alignof__ __alignof
# define alloca _alloca
#else
# ifndef HAVE_ALIGNOF
# include <stddef.h>
Expand Down Expand Up @@ -370,16 +369,23 @@ char * php_sha256_crypt_r(const char *key, const char *salt, char *buffer, int b

salt_len = MIN(strcspn(salt, "$"), SALT_LEN_MAX);
key_len = strlen(key);
char *tmp_key = NULL;
ALLOCA_FLAG(use_heap_key);
char *tmp_salt = NULL;
ALLOCA_FLAG(use_heap_salt);

SET_ALLOCA_FLAG(use_heap_key);
SET_ALLOCA_FLAG(use_heap_salt);

if ((key - (char *) 0) % __alignof__ (uint32_t) != 0) {
char *tmp = (char *) alloca(key_len + __alignof__(uint32_t));
key = copied_key = memcpy(tmp + __alignof__(uint32_t) - (tmp - (char *) 0) % __alignof__(uint32_t), key, key_len);
tmp_key = (char *) do_alloca(key_len + __alignof__(uint32_t), use_heap_key);
key = copied_key = memcpy(tmp_key + __alignof__(uint32_t) - (tmp_key - (char *) 0) % __alignof__(uint32_t), key, key_len);
}

if ((salt - (char *) 0) % __alignof__(uint32_t) != 0) {
char *tmp = (char *) alloca(salt_len + 1 + __alignof__(uint32_t));
tmp_salt = (char *) do_alloca(salt_len + 1 + __alignof__(uint32_t), use_heap_salt);
salt = copied_salt =
memcpy(tmp + __alignof__(uint32_t) - (tmp - (char *) 0) % __alignof__ (uint32_t), salt, salt_len);
memcpy(tmp_salt + __alignof__(uint32_t) - (tmp_salt - (char *) 0) % __alignof__ (uint32_t), salt, salt_len);
copied_salt[salt_len] = 0;
}

Expand Down Expand Up @@ -443,7 +449,8 @@ char * php_sha256_crypt_r(const char *key, const char *salt, char *buffer, int b
sha256_finish_ctx(&alt_ctx, temp_result);

/* Create byte sequence P. */
cp = p_bytes = alloca(key_len);
ALLOCA_FLAG(use_heap_p_bytes);
cp = p_bytes = do_alloca(key_len, use_heap_p_bytes);
for (cnt = key_len; cnt >= 32; cnt -= 32) {
cp = __php_mempcpy((void *)cp, (const void *)temp_result, 32);
}
Expand All @@ -461,7 +468,8 @@ char * php_sha256_crypt_r(const char *key, const char *salt, char *buffer, int b
sha256_finish_ctx(&alt_ctx, temp_result);

/* Create byte sequence S. */
cp = s_bytes = alloca(salt_len);
ALLOCA_FLAG(use_heap_s_bytes);
cp = s_bytes = do_alloca(salt_len, use_heap_s_bytes);
for (cnt = salt_len; cnt >= 32; cnt -= 32) {
cp = __php_mempcpy(cp, temp_result, 32);
}
Expand Down Expand Up @@ -571,6 +579,14 @@ char * php_sha256_crypt_r(const char *key, const char *salt, char *buffer, int b
if (copied_salt != NULL) {
ZEND_SECURE_ZERO(copied_salt, salt_len);
}
if (tmp_key != NULL) {
free_alloca(tmp_key, use_heap_key);
}
if (tmp_salt != NULL) {
free_alloca(tmp_salt, use_heap_salt);
}
free_alloca(p_bytes, use_heap_p_bytes);
free_alloca(s_bytes, use_heap_s_bytes);

return buffer;
}
Expand Down
30 changes: 23 additions & 7 deletions ext/standard/crypt_sha512.c
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Expand Up @@ -9,7 +9,6 @@
#include <limits.h>
#ifdef PHP_WIN32
# define __alignof__ __alignof
# define alloca _alloca
#else
# ifndef HAVE_ALIGNOF
# include <stddef.h>
Expand Down Expand Up @@ -404,16 +403,23 @@ php_sha512_crypt_r(const char *key, const char *salt, char *buffer, int buflen)

salt_len = MIN(strcspn(salt, "$"), SALT_LEN_MAX);
key_len = strlen(key);
char *tmp_key = NULL;
ALLOCA_FLAG(use_heap_key);
char *tmp_salt = NULL;
ALLOCA_FLAG(use_heap_salt);

SET_ALLOCA_FLAG(use_heap_key);
SET_ALLOCA_FLAG(use_heap_salt);

if ((key - (char *) 0) % __alignof__ (uint64_t) != 0) {
char *tmp = (char *) alloca (key_len + __alignof__ (uint64_t));
tmp_key = (char *) do_alloca(key_len + __alignof__ (uint64_t), use_heap_key);
key = copied_key =
memcpy(tmp + __alignof__(uint64_t) - (tmp - (char *) 0) % __alignof__(uint64_t), key, key_len);
memcpy(tmp_key + __alignof__(uint64_t) - (tmp_key - (char *) 0) % __alignof__(uint64_t), key, key_len);
}

if ((salt - (char *) 0) % __alignof__ (uint64_t) != 0) {
char *tmp = (char *) alloca(salt_len + 1 + __alignof__(uint64_t));
salt = copied_salt = memcpy(tmp + __alignof__(uint64_t) - (tmp - (char *) 0) % __alignof__(uint64_t), salt, salt_len);
tmp_salt = (char *) do_alloca(salt_len + 1 + __alignof__(uint64_t), use_heap_salt);
salt = copied_salt = memcpy(tmp_salt + __alignof__(uint64_t) - (tmp_salt - (char *) 0) % __alignof__(uint64_t), salt, salt_len);
copied_salt[salt_len] = 0;
}

Expand Down Expand Up @@ -477,7 +483,8 @@ php_sha512_crypt_r(const char *key, const char *salt, char *buffer, int buflen)
sha512_finish_ctx(&alt_ctx, temp_result);

/* Create byte sequence P. */
cp = p_bytes = alloca(key_len);
ALLOCA_FLAG(use_heap_p_bytes);
cp = p_bytes = do_alloca(key_len, use_heap_p_bytes);
for (cnt = key_len; cnt >= 64; cnt -= 64) {
cp = __php_mempcpy((void *) cp, (const void *)temp_result, 64);
}
Expand All @@ -496,7 +503,8 @@ php_sha512_crypt_r(const char *key, const char *salt, char *buffer, int buflen)
sha512_finish_ctx(&alt_ctx, temp_result);

/* Create byte sequence S. */
cp = s_bytes = alloca(salt_len);
ALLOCA_FLAG(use_heap_s_bytes);
cp = s_bytes = do_alloca(salt_len, use_heap_s_bytes);
for (cnt = salt_len; cnt >= 64; cnt -= 64) {
cp = __php_mempcpy(cp, temp_result, 64);
}
Expand Down Expand Up @@ -618,6 +626,14 @@ php_sha512_crypt_r(const char *key, const char *salt, char *buffer, int buflen)
if (copied_salt != NULL) {
ZEND_SECURE_ZERO(copied_salt, salt_len);
}
if (tmp_key != NULL) {
free_alloca(tmp_key, use_heap_key);
}
if (tmp_salt != NULL) {
free_alloca(tmp_salt, use_heap_salt);
}
free_alloca(p_bytes, use_heap_p_bytes);
free_alloca(s_bytes, use_heap_s_bytes);

return buffer;
}
Expand Down
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