llvm-mirror/test/CodeGen/AArch64/overlapping-copy-bundle-cycle.mir
Justin Bogner b10d38fe26 Re-apply "[VirtRegRewriter] Avoid clobbering registers when expanding copy bundles"
This is r334750 (which was reverted in r334754) with a fix for an
uninitialized variable that was caught by msan.

Original commit message:
> If a copy bundle happens to involve overlapping registers, we can end
> up with emitting the copies in an order that ends up clobbering some
> of the subregisters. Since instructions in the copy bundle
> semantically happen at the same time, this is incorrect and we need to
> make sure we order the copies such that this doesn't happen.

llvm-svn: 334756
2018-06-14 19:24:03 +00:00

17 lines
442 B
YAML

# RUN: not llc -mtriple=aarch64-apple-ios -run-pass=greedy -run-pass=virtregrewriter %s -o /dev/null 2>&1 | FileCheck %s
# Check we don't infinitely loop on cycles in copy bundles.
# CHECK: error: register rewriting failed: cycle in copy bundle
---
name: func0
body: |
bb.0:
$x0 = IMPLICIT_DEF
$q0_q1_q2_q3 = IMPLICIT_DEF
$q1_q2_q3 = COPY $q0_q1_q2 {
$q2_q3_q4 = COPY $q1_q2_q3
}
ST4i64 $q1_q2_q3_q4, 0, $x0
...