diff options
| -rw-r--r-- | lib/Target/README.txt | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/lib/Target/README.txt b/lib/Target/README.txt index 63f1f79962..33941f451a 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -2074,11 +2074,12 @@ for.end: ; preds = %entry } This shouldn't need the ((zext (%n - 1)) + 1) game, and it should ideally fold -the two memset's together. The issue with %n seems to stem from poor handling -of the original loop. +the two memset's together. -To simplify this, we need SCEV to know that "n != 0" because of the dominating -conditional. That would turn the second memset into a simple memset of 'n'. +The issue with the addition only occurs in 64-bit mode, and appears to be at +least partially caused by Scalar Evolution not keeping its cache updated: it +returns the "wrong" result immediately after indvars runs, but figures out the +expected result if it is run from scratch on IR resulting from running indvars. //===---------------------------------------------------------------------===// |