Add cachegrind support for php-cgi warmups

Cachegrind supports cg_annotate --diff, which makes it much easier to compare
the performance of two patches.

Author: iluuu1994

sapi/cgi/cgi_main.c

@@ -93,6 +93,7 @@ int __riscosify_control = __RISCOSIFY_STRICT_UNIX_SPECS;
 
 #ifdef HAVE_VALGRIND
 # include "valgrind/callgrind.h"
+# include "valgrind/cachegrind.h"
 #endif
 
 #ifndef PHP_WIN32
@@ -2247,8 +2248,10 @@ consult the installation file that came with this distribution, or visit \n\
 #ifdef HAVE_VALGRIND
 							if (warmup_repeats > 0) {
 								CALLGRIND_STOP_INSTRUMENTATION;
+								CACHEGRIND_STOP_INSTRUMENTATION;
 								/* We're not interested in measuring startup */
 								CALLGRIND_ZERO_STATS;
+								/* Zeroing stats is not supported for cachegrind. */
 							}
 #endif
 						} else {
@@ -2461,6 +2464,7 @@ consult the installation file that came with this distribution, or visit \n\
 #ifdef HAVE_VALGRIND
 			if (warmup_repeats == 0) {
 				CALLGRIND_START_INSTRUMENTATION;
+				CACHEGRIND_START_INSTRUMENTATION;
 			}
 #endif
 
@@ -2585,6 +2589,7 @@ consult the installation file that came with this distribution, or visit \n\
 #ifdef HAVE_VALGRIND
 			/* We're not interested in measuring shutdown */
 			CALLGRIND_STOP_INSTRUMENTATION;
+			CACHEGRIND_STOP_INSTRUMENTATION;
 #endif
 
 			if (!fastcgi) {