[PATCH 14/25] pickaxe -S: remove redundant "sz" check in while-loop

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Feb 3, 2021, 03:28 UTC
Message-ID: <20210203032811.14979-15-avarab@gmail.com>
In-Reply-To: <20210203032811.14979-1-avarab@gmail.com>

If we walk to the end of the string we just won't match the rest of the regex. This removes an optimization for simplicity's sake. In subsequent commits we'll alter this code more, and not having to think about this condition makes it easier to read.

If we look at the context of what we're doing here the last thing we need to be worried about is one extra regex match. The real problem is that we keep matching after it's clear that the number of contains() for "A" and "B" is different. So we could be much smarter here.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 diffcore-pickaxe.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/diffcore-pickaxe.c b/diffcore-pickaxe.c
index 208177bb40..8df76afb6e 100644
--- a/diffcore-pickaxe.c
+++ b/diffcore-pickaxe.c
@@ -82,12 +82,11 @@ static unsigned int contains(mmfile_t *mf, regex_t *regexp, kwset_t kws)
 		regmatch_t regmatch;
 		int flags = 0;
 
-		while (sz &&
-		       !regexec_buf(regexp, data, sz, 1, &regmatch, flags)) {
+		while (!regexec_buf(regexp, data, sz, 1, &regmatch, flags)) {
 			flags |= REG_NOTBOL;
 			data += regmatch.rm_eo;
 			sz -= regmatch.rm_eo;
-			if (sz && regmatch.rm_so == regmatch.rm_eo) {
+			if (regmatch.rm_so == regmatch.rm_eo) {
 				data++;
 				sz--;
 			}

-- 
2.30.0.284.gd98b1dd5eaa7