+#define POSCACHE_SUCCESS 0 /* caching success rather than failure */
+#define POSCACHE_SEEN 1 /* we know what we're caching */
+#define POSCACHE_START 2 /* the real cache: this bit maps to pos 0 */
+#define CACHEsayYES STMT_START { \
+ if (cache_offset | cache_bit) { \
+ if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
+ PL_reg_poscache[0] |= (1<<POSCACHE_SUCCESS) || (1<<POSCACHE_SEEN); \
+ else if (!(PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
+ /* cache records failure, but this is success */ \
+ DEBUG_r( \
+ PerlIO_printf(Perl_debug_log, \
+ "%*s (remove success from failure cache)\n", \
+ REPORT_CODE_OFF+PL_regindent*2, "") \
+ ); \
+ PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+ } \
+ } \
+ sayYES; \
+} STMT_END
+#define CACHEsayNO STMT_START { \
+ if (cache_offset | cache_bit) { \
+ if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
+ PL_reg_poscache[0] |= (1<<POSCACHE_SEEN); \
+ else if ((PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
+ /* cache records success, but this is failure */ \
+ DEBUG_r( \
+ PerlIO_printf(Perl_debug_log, \
+ "%*s (remove failure from success cache)\n", \
+ REPORT_CODE_OFF+PL_regindent*2, "") \
+ ); \
+ PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+ } \
+ } \
+ sayNO; \
+} STMT_END
+