2 Commits

Author	SHA1	Message	Date
Roman Lebedev	75404fb9f8	[InstCombine] Inefficient pattern for high-bits checking (PR38708) ... Summary: It is sometimes important to check that some newly-computed value is non-negative and only `n` bits wide (where `n` is a variable.) There are **many** ways to check that: https://godbolt.org/z/o4RB8D The last variant seems best? (I'm sure there are some other variations i haven't thought of..) Let's handle the second variant first, since it is much simpler. https://rise4fun.com/Alive/LYjY https://bugs.llvm.org/show_bug.cgi?id=38708 Reviewers: spatel, craig.topper, RKSimon Reviewed By: spatel Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D51985 llvm-svn: 342067	2018-09-12 18:19:43 +00:00
Roman Lebedev	99359f391e	[NFC][InstCombine] R38708 - inefficient pattern for high-bits checking. ... The simplest pattern for now: https://rise4fun.com/Alive/LYjY https://godbolt.org/z/o4RB8D https://bugs.llvm.org/show_bug.cgi?id=38708 llvm-svn: 342054	2018-09-12 14:11:37 +00:00