Commit Graph

3 Commits

Author SHA1 Message Date
Meera Nakrani dd519bf0b0 [ARM] Selects SSAT/USAT from correct LLVM IR
LLVM will canonicalize conditional selectors to a different pattern than the old code that was used.
This is updating the function to match the new expected patterns and select SSAT or USAT when successful.
Tests have also been updated to use the new patterns.

Differential Review: https://reviews.llvm.org/D87379
2020-09-14 10:58:21 +00:00
Renato Golin 32b165f561 [ARM] Saturation instructions are DSP-only
The saturation instructions appeared in v6T2, with DSP extensions, but they
were being accepted / generated on any, with the new introduction of the
saturation detection in the back-end. This commit restricts the usage to
DSP-enable only cores.

Fixes PR28607.

llvm-svn: 276701
2016-07-25 22:25:25 +00:00
Pablo Barrio 7a64346533 [ARM] Lower (select_cc k k (select_cc ~k ~k x)) into (SSAT l_k x)
Summary:
SSAT saturates an integer, making sure that its value lies within
an interval [-k, k]. Since the constant is given to SSAT as the
number of bytes set to one, k + 1 must be a power of 2, otherwise
the optimization is not possible. Also, the select_cc must use <
and > respectively so that they define an interval.

Reviewers: mcrosier, jmolloy, rengolin

Subscribers: aemerson, rengolin, llvm-commits

Differential Revision: http://reviews.llvm.org/D21372

llvm-svn: 273581
2016-06-23 16:53:49 +00:00