Artur Pilipenko 2bac40ee1c [IndVarSimplify] Use control-dependent range information to prove non-negativity ... This change is motivated by the case when IndVarSimplify doesn't widen a comparison of IV increment because it can't prove IV increment being non-negative. We end up with a redundant trunc of the widened increment on this example. for.body: %i = phi i32 [ %start, %for.body.lr.ph ], [ %i.inc, %for.inc ] %within_limits = icmp ult i32 %i, 64 br i1 %within_limits, label %continue, label %for.end continue: %i.i64 = zext i32 %i to i64 %arrayidx = getelementptr inbounds i32, i32* %base, i64 %i.i64 %val = load i32, i32* %arrayidx, align 4 br label %for.inc for.inc: %i.inc = add nsw nuw i32 %i, 1 %cmp = icmp slt i32 %i.inc, %limit br i1 %cmp, label %for.body, label %for.end There is a range check inside of the loop which guarantees the IV to be non-negative. NSW on the increment guarantees that the increment is also non-negative. Teach IndVarSimplify to use the range check to prove non-negativity of loop increments. Reviewed By: sanjoy Differential Revision: https://reviews.llvm.org/D25738 llvm-svn: 284629		2016-10-19 18:59:03 +00:00
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Coroutines	[coroutines] Store an address of destroy OR cleanup part in the coroutine frame.	2016-10-08 00:22:50 +00:00
Hello	Add auto-exporting of symbols from tools so that plugins work on Windows	2016-05-26 11:16:43 +00:00
InstCombine	[InstCombine] use m_APInt to allow sub with constant folds for splat vectors	2016-10-14 16:31:54 +00:00
Instrumentation	[asan] Simplify calculation of stack frame layout extraction calculation of stack description into separate function.	2016-10-18 23:29:52 +00:00
IPO	Conditionally eliminate library calls where the result value is not used	2016-10-18 21:36:27 +00:00
ObjCARC	Use StringRef in ARCRuntimeEntryPoints APIs (NFC)	2016-10-05 01:15:04 +00:00
Scalar	[IndVarSimplify] Use control-dependent range information to prove non-negativity	2016-10-19 18:59:03 +00:00
Utils	[asan] Replace std::to_string with llvm::to_string	2016-10-19 00:16:56 +00:00
Vectorize	[LV] Account for predicated stores in instruction costs	2016-10-13 14:54:31 +00:00
CMakeLists.txt	[coroutines] Part 3 of N: Adding Boilerplate for Coroutine Passes	2016-07-28 21:04:31 +00:00
LLVMBuild.txt	[coroutines] Part 3 of N: Adding Boilerplate for Coroutine Passes	2016-07-28 21:04:31 +00:00