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Commit Graph

Author	SHA1	Message	Date
Zhaoshi Zheng	e3c9070f06	Model ashr(shl(x, n), m) as mul(x, 2^(n-m)) when n > m Given below case: %y = shl %x, n %z = ashr %y, m when n = m, SCEV models it as sext(trunc(x)). This patch tries to handle the case where n > m by using sext(mul(trunc(x), 2^(n-m)))) as the SCEV expression. llvm-svn: 298631	2017-03-23 18:06:09 +00:00

Author

SHA1

Message

Date

Zhaoshi Zheng

e3c9070f06

Model ashr(shl(x, n), m) as mul(x, 2^(n-m)) when n > m

Given below case:

  %y = shl %x, n
  %z = ashr %y, m

when n = m, SCEV models it as sext(trunc(x)). This patch tries to handle
the case where n > m by using sext(mul(trunc(x), 2^(n-m)))) as the SCEV
expression.

llvm-svn: 298631

2017-03-23 18:06:09 +00:00

1 Commits