From ad8a1be529ea9e0bd6346a3cb1d53fec16e3bd10 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Fri, 11 Dec 2020 09:08:42 +0000 Subject: diffcore-rename: simplify limit check diffcore-rename had two different checks of the form if ((a < limit || b < limit) && a * b <= limit * limit) This can be simplified to if (st_mult(a, b) <= st_mult(limit, limit)) which makes it clearer how we are checking for overflow, and makes it much easier to parse given the drop from 8 to 4 variable appearances. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- diffcore-rename.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'diffcore-rename.c') diff --git a/diffcore-rename.c b/diffcore-rename.c index 1d6675c040..16553ab259 100644 --- a/diffcore-rename.c +++ b/diffcore-rename.c @@ -447,12 +447,16 @@ static int too_many_rename_candidates(int num_destinations, int num_sources, * growing larger than a "rename_limit" square matrix, ie: * * num_destinations * num_sources > rename_limit * rename_limit + * + * We use st_mult() to check overflow conditions; in the + * exceptional circumstance that size_t isn't large enough to hold + * the multiplication, the system won't be able to allocate enough + * memory for the matrix anyway. */ if (rename_limit <= 0) rename_limit = 32767; - if ((num_destinations <= rename_limit || num_sources <= rename_limit) && - ((uint64_t)num_destinations * (uint64_t)num_sources - <= (uint64_t)rename_limit * (uint64_t)rename_limit)) + if (st_mult(num_destinations, num_sources) + <= st_mult(rename_limit, rename_limit)) return 0; options->needed_rename_limit = @@ -468,9 +472,8 @@ static int too_many_rename_candidates(int num_destinations, int num_sources, continue; limited_sources++; } - if ((num_destinations <= rename_limit || limited_sources <= rename_limit) && - ((uint64_t)num_destinations * (uint64_t)limited_sources - <= (uint64_t)rename_limit * (uint64_t)rename_limit)) + if (st_mult(num_destinations, limited_sources) + <= st_mult(rename_limit, rename_limit)) return 2; return 1; } -- cgit v1.2.3