Chandler Carruth 5ea4a54551 [LPM] Fix PR18616 where the shifts to the loop pass manager to extract ... LCSSA from it caused a crasher with the LoopUnroll pass. This crasher is really nasty. We destroy LCSSA form in a suprising way. When unrolling a loop into an outer loop, we not only need to restore LCSSA form for the outer loop, but for all children of the outer loop. This is somewhat obvious in retrospect, but hey! While this seems pretty heavy-handed, it's not that bad. Fundamentally, we only do this when we unroll a loop, which is already a heavyweight operation. We're unrolling all of these hypothetical inner loops as well, so their size and complexity is already on the critical path. This is just adding another pass over them to re-canonicalize. I have a test case from PR18616 that is great for reproducing this, but pretty useless to check in as it relies on many 10s of nested empty loops that get unrolled and deleted in just the right order. =/ What's worse is that investigating this has exposed another source of failure that is likely to be even harder to test. I'll try to come up with test cases for these fixes, but I want to get the fixes into the tree first as they're causing crashes in the wild. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200273 91177308-0d34-0410-b5e6-96231b3b80d8		2014-01-28 01:25:38 +00:00
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Analysis	Fix crasher introduced in r200203 and caught by a libc++ buildbot. Don't assume that getMulExpr returns a SCEVMulExpr, it may have simplified it to something else!	2014-01-27 10:47:44 +00:00
AsmParser	Add an inalloca flag to allocas	2014-01-17 23:58:17 +00:00
Bitcode	Make parseBitcodeFile return an ErrorOr<Module *>.	2014-01-15 01:08:23 +00:00
CodeGen	[TLI] Add a new hook to TargetLowering to query the target if a load of a constant should be converted to simply the constant itself.	2014-01-28 01:20:14 +00:00
DebugInfo	[Sparc] Add support for parsing DW_CFA_GNU_window_save.	2014-01-26 05:13:44 +00:00
ExecutionEngine	Fix known typos	2014-01-24 17:20:08 +00:00
IR	Fix llvm-dis to print the inalloca bit on allocas.	2014-01-25 01:24:06 +00:00
IRReader	Make parseBitcodeFile return an ErrorOr<Module *>.	2014-01-15 01:08:23 +00:00
Linker	Reapply r194218 with fix:	2014-01-16 06:29:36 +00:00
LTO	Construct the MCStreamer before constructing the MCTargetStreamer.	2014-01-26 06:06:37 +00:00
MC	MC: Add support for .cfi_startproc simple	2014-01-27 17:20:25 +00:00
Object	llvm-readobj: add support for PE32+ (Windows 64 bit executable).	2014-01-26 04:15:52 +00:00
Option	Avoid buffer copies when a Twine already is a StringRef.	2013-12-03 18:18:28 +00:00
Support	Fix the "#ifndef HAVE_SYS_WAIT_H" code path in Program.inc to compile	2014-01-27 22:53:07 +00:00
TableGen	[TableGen] Correctly generate implicit anonymous prototype defs in multiclasses	2014-01-02 20:47:09 +00:00
Target	[TLI] Add a new hook to TargetLowering to query the target if a load of a constant should be converted to simply the constant itself.	2014-01-28 01:20:14 +00:00
Transforms	[LPM] Fix PR18616 where the shifts to the loop pass manager to extract	2014-01-28 01:25:38 +00:00
CMakeLists.txt	Move LTO support library to a component, allowing it to be tested	2013-09-24 23:52:22 +00:00
LLVMBuild.txt	Move LTO support library to a component, allowing it to be tested	2013-09-24 23:52:22 +00:00
Makefile	Reformat Makefile. No other changes.	2013-10-30 04:03:03 +00:00