Chandler Carruth 03300ecaee Move the handling of unanalyzable branches out of the loop-driven chain ... formation phase and into the initial walk of the basic blocks. We essentially pre-merge all blocks where unanalyzable fallthrough exists, as we won't be able to update the terminators effectively after any reorderings. This is quite a bit more principled as there may be CFGs where the second half of the unanalyzable pair has some analyzable predecessor that gets placed first. Then it may get placed next, implicitly breaking the unanalyzable branch even though we never even looked at the part that isn't analyzable. I've included a test case that triggers this (thanks Benjamin yet again!), and I'm hoping to synthesize some more general ones as I dig into related issues. Also, to make this new scheme work we have to be able to handle branches into the middle of a chain, so add this check. We always fallback on the incoming ordering. Finally, this starts to really underscore a known limitation of the current implementation -- we don't consider broken predecessors when merging successors. This can caused major missed opportunities, and is something I'm planning on looking at next (modulo more bug reports). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144994 91177308-0d34-0410-b5e6-96231b3b80d8		2011-11-19 10:26:02 +00:00
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ARM	When fast iseling a GEP, accumulate the offset rather than emitting a series of	2011-11-17 07:15:58 +00:00
CBackend	Only run tests in test/CodeGen/CBackend/X86 when both X86 and CBackend are supported	2011-09-26 06:44:27 +00:00
CellSPU	Remove histogram tests.	2011-11-12 22:39:40 +00:00
CPP	manually upgrade a bunch of tests to modern syntax, and remove some that	2011-06-17 03:14:27 +00:00
Generic	Remove the the test which checks the saving of a vector of booleans into memory.	2011-10-16 19:06:06 +00:00
MBlaze	Change the default scheduler from Latency to ILP, since Latency	2011-10-24 17:45:02 +00:00
Mips	Reapply r143206, with fixes. Disallow physical register lifetimes	2011-11-03 21:49:52 +00:00
MSP430	Remove the explicit request for "Latency" scheduling from MSP430,	2011-10-24 17:53:16 +00:00
PowerPC	test/CodeGen/PowerPC/2008-10-17-AsmMatchingOperands.ll: [PR11218] Mark "REQUIRES: asserts" for now.	2011-10-28 23:11:03 +00:00
PTX	allow non-device function calls in PTX when natively handling device-side printf	2011-11-11 14:45:12 +00:00
SPARC	make the asmparser reject function and type redefinitions. 'Merging' hasn't been	2011-06-17 07:06:44 +00:00
Thumb	Reapply r143206, with fixes. Disallow physical register lifetimes	2011-11-03 21:49:52 +00:00
Thumb2	Add vmov.f32 to materialize f32 immediate splats which cannot be handled by	2011-11-15 02:12:34 +00:00
X86	Move the handling of unanalyzable branches out of the loop-driven chain	2011-11-19 10:26:02 +00:00
XCore	Don't fold negative offsets into cp / dp accesses to avoid relocation errors.	2011-11-01 11:31:53 +00:00