llvm-project/llvm
Craig Topper 2c20c42cb6 [JumpThreading] Teach jump threading how to analyze (and (cmp A, C1), (cmp A, C2)) after InstCombine has turned it into (cmp (add A, C3), C4)
Currently JumpThreading can use LazyValueInfo to analyze an 'and' or 'or' of compare if the compare is fed by a livein of a basic block. This can be used to to prove the condition can't be met for some predecessor and the jump from that predecessor can be moved to the false path of the condition.

But if the compare is something that InstCombine turns into an add and a single compare, it can't be analyzed because the livein is now an input to the add and not the compare.

This patch adds a new method to LVI to get a ConstantRange on an edge. Then we teach jump threading to detect the add livein feeding a compare and to get the ConstantRange and propagate it.

Differential Revision: https://reviews.llvm.org/D33262

llvm-svn: 306085
2017-06-23 05:41:35 +00:00
..
bindings [Go] Subtypes function 2017-06-08 07:32:29 +00:00
cmake TableGen.cmake: Use DEPFILE for Ninja Generator with CMake>=3.7. 2017-06-21 22:04:07 +00:00
docs Define behavior of "stack-probe-size" attribute when inlining. 2017-06-22 23:22:36 +00:00
examples [ORC] Switch the object layer API from addObjectSet to addObject (singular), and 2017-06-22 21:06:54 +00:00
include [JumpThreading] Teach jump threading how to analyze (and (cmp A, C1), (cmp A, C2)) after InstCombine has turned it into (cmp (add A, C3), C4) 2017-06-23 05:41:35 +00:00
lib [JumpThreading] Teach jump threading how to analyze (and (cmp A, C1), (cmp A, C2)) after InstCombine has turned it into (cmp (add A, C3), C4) 2017-06-23 05:41:35 +00:00
projects Add temporary workaround to allow in-tree libc++ builds on Windows 2017-05-11 01:44:30 +00:00
resources
runtimes [CMake][runtimes] Add install target for runtimes builtins 2017-06-02 19:38:11 +00:00
test COFF: Produce an error on invalid pcrel relocs. 2017-06-23 04:07:44 +00:00
tools [ORC] Switch the object layer API from addObjectSet to addObject (singular), and 2017-06-22 21:06:54 +00:00
unittests [ORC] Switch the object layer API from addObjectSet to addObject (singular), and 2017-06-22 21:06:54 +00:00
utils [TableGen] Take a parameter by reference instead of pointer so we don't have to add & on both callers. NFC 2017-06-20 16:34:37 +00:00
.arcconfig
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt [Solaris] replace Solaris.h hack with a set of better hacks 2017-06-22 13:18:46 +00:00
CODE_OWNERS.TXT
CREDITS.TXT update of the url 2017-05-14 07:55:01 +00:00
LICENSE.TXT
LLVMBuild.txt
README.txt
RELEASE_TESTERS.TXT
configure
llvm.spec.in

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