Dan Gohman 2c74fe977d Add an @llvm.sideeffect intrinsic ... This patch implements Chandler's idea [0] for supporting languages that require support for infinite loops with side effects, such as Rust, providing part of a solution to bug 965 [1]. Specifically, it adds an `llvm.sideeffect()` intrinsic, which has no actual effect, but which appears to optimization passes to have obscure side effects, such that they don't optimize away loops containing it. It also teaches several optimization passes to ignore this intrinsic, so that it doesn't significantly impact optimization in most cases. As discussed on llvm-dev [2], this patch is the first of two major parts. The second part, to change LLVM's semantics to have defined behavior on infinite loops by default, with a function attribute for opting into potential-undefined-behavior, will be implemented and posted for review in a separate patch. [0] http://lists.llvm.org/pipermail/llvm-dev/2015-July/088103.html [1] https://bugs.llvm.org/show_bug.cgi?id=965 [2] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118632.html Differential Revision: https://reviews.llvm.org/D38336 llvm-svn: 317729		2017-11-08 21:59:51 +00:00
..
2002-04-14-UnexpectedUnsignedType.ll	…
2002-04-16-StackFrameSizeAlignment.ll	…
2003-05-27-phifcmpd.ll	…
2003-05-27-useboolinotherbb.ll	…
2003-05-27-usefsubasbool.ll	…
2003-05-28-ManyArgs.ll	…
2003-05-30-BadFoldGEP.ll	…
2003-05-30-BadPreselectPhi.ll	…
2003-07-06-BadIntCmp.ll	…
2003-07-07-BadLongConst.ll	…
2003-07-08-BadCastToBool.ll	…
2003-07-29-BadConstSbyte.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
2004-05-09-LiveVarPartialRegister.ll	…
2005-01-18-SetUO-InfLoop.ll	…
2005-04-09-GlobalInPHI.ll	…
2005-10-18-ZeroSizeStackObject.ll	…
2005-10-21-longlonggtu.ll	…
2005-12-01-Crash.ll	…
2005-12-12-ExpandSextInreg.ll	…
2006-01-12-BadSetCCFold.ll	…
2006-01-18-InvalidBranchOpcodeAssert.ll	…
2006-02-12-InsertLibcall.ll	…
2006-03-01-dagcombineinfloop.ll	…
2006-04-26-SetCCAnd.ll	…
2006-04-28-Sign-extend-bool.ll	…
2006-05-06-GEP-Cast-Sink-Crash.ll	…
2006-06-12-LowerSwitchCrash.ll	…
2006-06-13-ComputeMaskedBitsCrash.ll	…
2006-06-28-SimplifySetCCCrash.ll	…
2006-07-03-schedulers.ll	…
2006-08-30-CoalescerCrash.ll	…
2006-09-02-LocalAllocCrash.ll	…
2006-09-06-SwitchLowering.ll	…
2006-10-27-CondFolding.ll	…
2006-10-29-Crash.ll	…
2006-11-20-DAGCombineCrash.ll	…
2007-01-15-LoadSelectCycle.ll	…
2007-02-25-invoke.ll	…
2007-04-08-MultipleFrameIndices.ll	[AVR] XFAIL a set of failing CodeGen tests	2017-02-08 10:24:18 +00:00
2007-04-13-SwitchLowerBadPhi.ll	…
2007-04-17-lsr-crash.ll	…
2007-04-27-InlineAsm-X-Dest.ll	…
2007-04-27-LargeMemObject.ll	…
2007-04-30-LandingPadBranchFolding.ll	…
2007-05-03-EHTypeInfo.ll	…
2007-05-15-InfiniteRecursion.ll	…
2007-12-17-InvokeAsm.ll	[AVR] XFAIL a set of failing CodeGen tests	2017-02-08 10:24:18 +00:00
2007-12-31-UnusedSelector.ll	…
2008-01-25-dag-combine-mul.ll	…
2008-01-30-LoadCrash.ll	…
2008-02-04-Ctlz.ll	…
2008-02-04-ExtractSubvector.ll	…
2008-02-20-MatchingMem.ll	…
2008-02-25-NegateZero.ll	…
2008-02-26-NegatableCrash.ll	…
2008-08-07-PtrToInt-SmallerInt.ll	…
2009-03-17-LSR-APInt.ll	…
2009-03-29-SoftFloatVectorExtract.ll	…
2009-04-10-SinkCrash.ll	…
2009-04-28-i128-cmp-crash.ll	…
2009-11-16-BadKillsCrash.ll	…
2010-07-27-DAGCombineCrash.ll	…
2010-11-04-BigByval.ll	…
2010-ZeroSizedArg.ll	…
2011-01-06-BigNumberCrash.ll	…
2011-07-07-ScheduleDAGCrash.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
2012-06-08-APIntCrash.ll	…
2013-03-20-APFloatCrash.ll	…
2014-02-05-OpaqueConstants.ll	…
APIntLoadStore.ll	…
APIntParam.ll	…
APIntSextParam.ll	…
APIntZextParam.ll	…
BasicInstrs.ll	…
ConstantExprLowering.ll	…
ForceStackAlign.ll	Revert "Change memcpy/memset/memmove to have dest and source alignments."	2015-11-19 05:56:52 +00:00
MachineBranchProb.ll	[ARM/AARCH64] Make test MachineBranchProb.ll more robust and re-enable for ARM/AArch64	2017-10-05 18:33:34 +00:00
PBQP.ll	…
add-with-overflow-24.ll	…
add-with-overflow-128.ll	…
add-with-overflow.ll	…
addr-label.ll	…
annotate.ll	…
asm-large-immediate.ll	…
assume.ll	…
badCallArgLRLLVM.ll	…
badFoldGEP.ll	…
badarg6.ll	…
bool-to-double.ll	…
builtin-expect.ll	…
call-ret0.ll	…
call-ret42.ll	…
call-void.ll	…
call2-ret0.ll	…
cast-fp.ll	…
cfi-sections.ll	PR 31534: When emitting both DWARF unwind tables and debug information,	2017-01-05 20:55:28 +00:00
constindices.ll	…
crash.ll	…
dag-combine-crash.ll	…
dbg_value.ll	…
div-neg-power-2.ll	…
donothing.ll	…
dont-remove-empty-preheader.ll	Add missing test for the "Don't delete empty preheaders" added in r265397	2016-04-05 14:21:32 +00:00
edge-bundles-blockIDs.ll	…
empty-insertvalue.ll	…
empty-load-store.ll	…
empty-phi.ll	…
exception-handling.ll	…
expand-experimental-reductions.ll	Add a late IR expansion pass for the experimental reduction intrinsics.	2017-05-10 09:42:49 +00:00
externally_available.ll	Do not verify MachimeDominatorTree if it is not calculated	2017-03-02 12:00:10 +00:00
fastcall.ll	…
fneg-fabs.ll	…
fp-to-int-invalid.ll	…
fp_to_int.ll	…
fpowi-promote.ll	…
fwdtwice.ll	…
global-ret0.ll	…
hello.ll	…
i128-addsub.ll	…
i128-arith.ll	…
icmp-illegal.ll	Remove an empty line in icmp-illegal.ll . NFC	2017-02-27 16:09:44 +00:00
inline-asm-mem-clobber.ll	[AVR] XFAIL a set of failing CodeGen tests	2017-02-08 10:24:18 +00:00
inline-asm-special-strings.ll	…
intrinsics.ll	Add an @llvm.sideeffect intrinsic	2017-11-08 21:59:51 +00:00
invalid-memcpy.ll	Revert "Change memcpy/memset/memmove to have dest and source alignments."	2015-11-19 05:56:52 +00:00
isunord.ll	…
lit.local.cfg	…
llc-start-stop.ll	re-land [ExpandMemCmp] Split ExpandMemCmp from CodeGen into its own pass."	2017-11-03 12:12:27 +00:00
llvm-ct-intrinsics.ll	…
multiple-return-values-cross-block-with-invoke.ll	[Hexagon] Unxfail passing tests	2017-04-13 16:05:35 +00:00
negintconst.ll	…
nested-select.ll	…
no-target.ll	…
opt-codegen-no-target-machine.ll	[LegacyPassManager] Remove TargetMachine constructors	2017-05-18 17:21:13 +00:00
overflow.ll	…
overloaded-intrinsic-name.ll	Only run the overloaded-intrinsic-name.ll test once, with FileCheck.	2017-03-01 01:56:41 +00:00
pr2625.ll	…
pr3288.ll	…
pr12507.ll	…
pr24662.ll	Fix constant folding of fp2int to large integers	2017-03-19 16:50:25 +00:00
pr33094.ll	Handle ConstantExpr correctly in SelectionDAGBuilder	2017-07-09 16:01:04 +00:00
print-add.ll	…
print-after.ll	…
print-arith-fp.ll	…
print-arith-int.ll	…
print-int.ll	…
print-machineinstrs.ll	[SystemZ] Fix trap issue and enable expensive checks.	2017-06-23 14:30:46 +00:00
print-mul-exp.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
print-mul.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
print-shift.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
ptr-annotate.ll	…
ret0.ll	…
ret42.ll	…
select-cc.ll	[Hexagon] Unxfail passing tests	2017-04-13 16:05:35 +00:00
select.ll	…
shift-int64.ll	…
stacksave-restore.ll	…
storetrunc-fp.ll	…
switch-lower-feature.ll	…
switch-lower.ll	…
trap.ll	…
undef-phi.ll	…
v-split.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
vector-casts.ll	…
vector-constantexpr.ll	…
vector-identity-shuffle.ll	…
vector-redux.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
vector.ll	[AVR] Add/remove XFAILs to get the backend passing Generic CodeGen tests	2017-07-16 23:33:50 +00:00
zero-probability.mir	[MIParser] Ensure getHexUint doesn't produce APInts with a bitwidth of 0	2017-09-01 22:17:14 +00:00
zero-sized-array.ll	…