https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126297
Bug ID: 126297
Summary: [17 Regression] Minor SH testsuite failure after
recent change
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: law at gcc dot gnu.org
Target Milestone: ---
This change causes a sh testsuite regression:
commit e46d96d20bbfa786d30c9371631da00939845f05 (HEAD)
Author: Roger Sayle <[email protected]>
Date: Wed Jul 15 12:26:16 2026 +0100
PR middle-end/123236: Simplify (int)((long long)x >> 4)
This patch addresses a code quality regression on x86_64 related to
PR 123236. That original PR (and the related PR 101266) concern tree
level optimizations, where this problem should also be fixed, but it
also reveals a regression in the RTL optimizers.
A motivating test case (on x86_64) is:
int bar(int a) {
long long t = a;
return t >> 4;
}
[ ... ]
On sh3-linux-gnu and sh3eb-linux-gnu:
Tests that now fail, but worked before (1 tests):
gcc: gcc.target/sh/pr64345-1.c scan-assembler-times shlr\t 8
If I diff the assembly before/after it looks like we're turning a shifts into
bit tests. That's probably an improvement, but I couldn't say with 100%
certainty.
