6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2026-04-26 12:20:42 +00:00
Code Issues Projects Releases Wiki Activity

[vectorizer] Completely disable the block frequency guidance of the loop

Browse Source 
vectorizer, placing it behind an off-by-default flag.

It turns out that block frequency isn't what we want at all, here or
elsewhere. This has been I think a nagging feeling for several of us
working with it, but Arnold has given some really nice simple examples
where the results are so comprehensively wrong that they aren't useful.

I'm planning to email the dev list with a summary of why its not really
useful and a couple of ideas about how to better structure these types
of heuristics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200294 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chandler Carruth
2014-01-28 09:10:41 +00:00
parent e5487fce5d
commit 05d43d8b6f
2 changed files with 14 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files
test/Transforms/LoopVectorize/X86/small-size.ll
+1 -1
View File
@@ -1,4 +1,4 @@
; RUN: opt < %s -loop-vectorize -force-vector-unroll=1 -force-vector-width=4 -dce -instcombine -S | FileCheck %s
; RUN: opt < %s -loop-vectorize -force-vector-unroll=1 -force-vector-width=4 -loop-vectorize-with-block-frequency -dce -instcombine -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"