llvm-project/llvm
Sanjoy Das 29a4b5dc0d [SCEV] Fix PR26207
In some cases, the max backedge taken count can be more conservative
than the exact backedge taken count (for instance, because
ScalarEvolution::getRange is not control-flow sensitive whereas
computeExitLimitFromICmp can be).  In these cases,
computeExitLimitFromCond (specifically the bit that deals with `and` and
`or` instructions) can create an ExitLimit instance with a
`SCEVCouldNotCompute` max backedge count expression, but a computable
exact backedge count expression.  This violates an implicit SCEV
assumption: a computable exact BE count should imply a computable max BE
count.

This change

 - Makes the above implicit invariant explicit by adding an assert to
   ExitLimit's constructor

 - Changes `computeExitLimitFromCond` to be more robust around
   conservative max backedge counts

llvm-svn: 258184
2016-01-19 20:53:51 +00:00
..
autoconf Update version to 3.9. 2016-01-13 17:32:32 +00:00
bindings Deprecate a few C APIs. 2015-12-18 23:46:42 +00:00
cmake Fix bootstrap -Werror builds after clang r258128 2016-01-19 20:52:17 +00:00
docs docs: address post-commit review 2016-01-19 05:43:21 +00:00
examples Fix examples corresponding to r257302. 2016-01-11 05:04:20 +00:00
include [SCEV] Fix PR26207 2016-01-19 20:53:51 +00:00
lib [SCEV] Fix PR26207 2016-01-19 20:53:51 +00:00
projects
resources
test [SCEV] Fix PR26207 2016-01-19 20:53:51 +00:00
tools Add a change accidentally left out from r258100 2016-01-18 23:35:24 +00:00
unittests [Orc] Revert r258031 - it broke the builders. 2016-01-18 01:51:51 +00:00
utils test-release.sh: Use CMake also for Darwin 2016-01-19 19:21:58 +00:00
.arcconfig
.clang-format
.clang-tidy adding readability-identifier-naming to llvm clang-tidy configuration. 2015-12-08 17:44:51 +00:00
.gitignore
CMakeLists.txt Update version to 3.9. 2016-01-13 17:32:32 +00:00
CODE_OWNERS.TXT The PS4 baton passes. 2015-12-19 20:04:03 +00:00
CREDITS.TXT
LICENSE.TXT
LLVMBuild.txt
Makefile
Makefile.common
Makefile.config.in
Makefile.rules
README.txt Revert previous test commit. 2016-01-04 19:13:29 +00:00
configure Update version to 3.9. 2016-01-13 17:32:32 +00:00
llvm.spec.in

README.txt

Low Level Virtual Machine (LLVM)
================================

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a toolkit for the construction of highly optimized compilers,
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LLVM is open source software. You may freely distribute it under the terms of
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Please see the documentation provided in docs/ for further
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If you are writing a package for LLVM, see docs/Packaging.rst for our
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