https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102448
Bug ID: 102448 Summary: [12 Regression] wrong codegen in gcc in spec2017 since 24f99147b9264f8f7d9cfb2fa6bd431edfa252d2 Product: gcc Version: 12.0 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: tnfchris at gcc dot gnu.org CC: rguenth at gcc dot gnu.org Target Milestone: --- Since g:24f99147b9264f8f7d9cfb2fa6bd431edfa252d2 we've been getting a segfault on gcc in spec2017. It looks like ira_init has been miscompiled and an additional unconditional store materialized: Before: add x1, x19, #0x4 add x2, x19, #0x14 ldr q0, [x0,#4064] str q0, [x1],#16 After: add x19, x19, #0x4 ldr q0, [x0,#4000] str q0, [x19],#16 str q0, [x19],#16 so it's pushing 16 bytes more into x19 than it did before. Trying to see if I can reduce a testcase