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| author | Qing Zhao <qing.zhao@oracle.com> | 2018-07-13 14:10:45 +0000 |
|---|---|---|
| committer | Qing Zhao <qinzhao@gcc.gnu.org> | 2018-07-13 14:10:45 +0000 |
| commit | b2272b138c1e7f6a1cb867d614951d516f88a9f1 (patch) | |
| tree | c0ff90bac1be9a15892993c77b7e1b8b791f2416 /gcc/params.def | |
| parent | b02160e5ac1dc57bbecd3387b61fcad8c7a57672 (diff) | |
| download | gcc-b2272b138c1e7f6a1cb867d614951d516f88a9f1.zip gcc-b2272b138c1e7f6a1cb867d614951d516f88a9f1.tar.gz gcc-b2272b138c1e7f6a1cb867d614951d516f88a9f1.tar.bz2 | |
3nd Patch for PR78009
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78809
Inline strcmp with small constant strings
The design doc for PR78809 is at:
https://www.mail-archive.com/gcc@gcc.gnu.org/msg83822.html
this patch is for the third part of change of PR78809.
C. for strcmp (s1, s2), strncmp (s1, s2, n), and memcmp (s1, s2, n)
if the result is NOT used to do simple equality test against zero, one of
"s1" or "s2" is a small constant string, n is a constant, and the Min value of
the length of the constant string and "n" is smaller than a predefined
threshold T,
inline the call by a byte-to-byte comparision sequence to avoid calling
overhead.
adding test case strcmpopt_5.c into gcc.dg for part C of PR78809.
adding test case strcmpopt_6.c into gcc.dg to test the following case:
When the specified length exceeds one of the arguments of the call to memcmp,
the call to memcmp should NOT be inlined.
From-SVN: r262636
Diffstat (limited to 'gcc/params.def')
| -rw-r--r-- | gcc/params.def | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/gcc/params.def b/gcc/params.def index a3906c2..df3a06b 100644 --- a/gcc/params.def +++ b/gcc/params.def @@ -446,6 +446,10 @@ DEFPARAM(BUILTIN_EXPECT_PROBABILITY, "builtin-expect-probability", "Set the estimated probability in percentage for builtin expect. The default value is 90% probability.", 90, 0, 100) +DEFPARAM(BUILTIN_STRING_CMP_INLINE_LENGTH, + "builtin-string-cmp-inline-length", + "The maximum length of a constant string for a builtin string cmp call eligible for inlining. The default value is 3.", + 3, 0, 100) DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK, "tracer-dynamic-coverage-feedback", "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available.", |