Sprintf optimize

[TimWolla]

No description provided.

[iluuu1994]

This misses the optimizations from zend_compile_encaps_list(), which concat()s adjacent string constants. I'm not sure how important this is for sprintf.

[TimWolla]

Fairly unimportant, I'd say: Using a placeholder to insert a constant string is not really the expected use case of sprintf().

FWIW: Opcache will automatically merge ropes that are completely constant:

<?php

var_dump(sprintf("%s: %s-%s", __FILE__, "foo", "bar"));

$ sapi/cli/php -d zend_extension=(pwd)/modules/opcache.so -d opcache.enable_cli=1 -d opcache.opt_debug_level=0x10000 test.php

$_main:
     ; (lines=9, args=0, vars=0, tmps=5)
     ; (before optimizer)
     ; php-src/test.php:1-4
     ; return  [] RANGE[0..0]
0000 INIT_FCALL 1 96 string("var_dump")
0001 T1 = ROPE_INIT 5 string("php-src/test.php")
0002 T1 = ROPE_ADD 1 T1 string(": ")
0003 T1 = ROPE_ADD 2 T1 string("foo")
0004 T1 = ROPE_ADD 3 T1 string("-")
0005 T0 = ROPE_END 4 T1 string("bar")
0006 SEND_VAL T0 1
0007 DO_ICALL
0008 RETURN int(1)
LIVE RANGES:
     1: 0001 - 0005 (rope)
string(25) "php-src/test.php: foo-bar"
$ sapi/cli/php -d zend_extension=(pwd)/modules/opcache.so -d opcache.enable_cli=1 -d opcache.opt_debug_level=0x20000 test.php

$_main:
     ; (lines=4, args=0, vars=0, tmps=0)
     ; (after optimizer)
     ; php-src/test.php:1-4
0000 INIT_FCALL 1 96 string("var_dump")
0001 SEND_VAL string("php-src/test.php: foo-bar") 1
0002 DO_ICALL
0003 RETURN int(1)
string(25) "php-src/test.php: foo-bar"

[iluuu1994]

Fair enough. This can always be added later. And if opcache takes care of it, it's likely fairly unimportant.