https://llvm.org/bugs/show_bug.cgi?id=25247
Bug ID: 25247
Summary: SLPVectorizer is sensitive to the order of operands
(commutative ops)
Product: new-bugs
Version: trunk
Hardware: PC
OS: All
Status: NEW
Severity: normal
Priority: P
Component: new bugs
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected]
Classification: Unclassified
Created attachment 15107
--> https://llvm.org/bugs/attachment.cgi?id=15107&action=edit
This IR will be vectorized
The two IR files attached shows the issue. The diff between the two files is
only the order of the operands to two xor operations.
363c363
< %284 = xor i8 %31, %283
---
> %284 = xor i8 %283, %31
401c401
< %306 = xor i8 %146, %283
---
> %306 = xor i8 %283, %146
In one case, reorderInputsAccordingToOpcode() will produce a splat on one-side,
which lead to a lower cost and triggers the vectorization.
--
You are receiving this mail because:
You are on the CC list for the bug.
_______________________________________________
llvm-bugs mailing list
[email protected]
http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
