Optimized access to temporary and compiled VM variables

php · Dec 4, 2012 · 7651d64 · 7651d64
1 parent 7848502
commit 7651d64
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Showing 12 changed files with 1,429 additions and 1,467 deletions.
diff --git a/NEWS b/NEWS
@@ -3,6 +3,8 @@ PHP                                                                        NEWS
 ?? ??? 201?, PHP 5.5.0
 
 - General improvements:
+  . Optimized access to temporary and compiled VM variables. 8% less memory
+    reads. (Dmitry)
   . The VM stacks for passing function arguments and syntaticaly nested calls
     were merged into a single stack. The stack size needed for op_array
     execution is calculated at compile time and preallocated at once. As result

diff --git a/UPGRADING b/UPGRADING
@@ -48,6 +48,17 @@ PHP 5.5 UPGRADE NOTES
   corresponding stack space is preallocated together with execute_data.
   ZEND_SEND* and ZEND_DO_FCALL* don't need to check for stack overflow
   anymore.
+- Removed execute_data->Ts field. The VM temporary variables always allocated
+  immediately before execute_data structure. Now they are accessed by offset
+  from the execute_data base pointer (instead of execute_data->Ts). Compiler
+  stores new offsets in op_array->opcodes[*].op?.num. You can use macros
+  EX_TMP_VAR() and EX_TMP_VAR_NUM() to access temp_variable by offset or
+  number. You can convert number to offset using EX_TMP_VAR_NUM(0, num) or
+  offset to number (EX_TMP_VAR(0,offset)-EX_TMP_VAR_NUM(0,0)).
+- Removed execute_data->CVs field. The VM compiled variables always allocated
+  immediately after execute_data structure. Now they are accessed by offset
+  from the execute_data base pointer (instead of execute_data->CVs). You can
+  use macros EX_CV_NUM() to access compiled variables by number.
 
 ========================================
 2. New Features

diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
@@ -287,7 +287,7 @@ ZEND_API zend_bool zend_is_compiling(TSRMLS_D) /* {{{ */
 
 static zend_uint get_temporary_variable(zend_op_array *op_array) /* {{{ */
 {
-	return (op_array->T)++ * ZEND_MM_ALIGNED_SIZE(sizeof(temp_variable));
+	return EX_TMP_VAR_NUM(0, (op_array->T)++);
 }
 /* }}} */
 

diff --git a/Zend/zend_compile.h b/Zend/zend_compile.h
@@ -387,8 +387,6 @@ struct _zend_execute_data {
 	zend_function_state function_state;
 	zend_op_array *op_array;
 	zval *object;
-	union _temp_variable *Ts;
-	zval ***CVs;
 	HashTable *symbol_table;
 	struct _zend_execute_data *prev_execute_data;
 	zval *old_error_reporting;
@@ -404,6 +402,11 @@ struct _zend_execute_data {
 
 #define EX(element) execute_data.element
 
+#define EX_TMP_VAR(ex, n)	   ((temp_variable*)(((char*)(ex)) + ((int)(n))))
+#define EX_TMP_VAR_NUM(ex, n)  (EX_TMP_VAR(ex, 0) - (1 + (n)))
+
+#define EX_CV_NUM(ex, n)       (((zval***)(((char*)(ex))+ZEND_MM_ALIGNED_SIZE(sizeof(zend_execute_data))))+(n))
+
 
 #define IS_CONST	(1<<0)
 #define IS_TMP_VAR	(1<<1)