Tim Northover b9ec29d7c5 IR: add "cmpxchg weak" variant to support permitted failure. ... This commit adds a weak variant of the cmpxchg operation, as described in C++11. A cmpxchg instruction with this modifier is permitted to fail to store, even if the comparison indicated it should. As a result, cmpxchg instructions must return a flag indicating success in addition to their original iN value loaded. Thus, for uniformity *all* cmpxchg instructions now return "{ iN, i1 }". The second flag is 1 when the store succeeded. At the DAG level, a new ATOMIC_CMP_SWAP_WITH_SUCCESS node has been added as the natural representation for the new cmpxchg instructions. It is a strong cmpxchg. By default this gets Expanded to the existing ATOMIC_CMP_SWAP during Legalization, so existing backends should see no change in behaviour. If they wish to deal with the enhanced node instead, they can call setOperationAction on it. Beware: as a node with 2 results, it cannot be selected from TableGen. Currently, no use is made of the extra information provided in this patch. Test updates are almost entirely adapting the input IR to the new scheme. Summary for out of tree users: ------------------------------ + Legacy Bitcode files are upgraded during read. + Legacy assembly IR files will be invalid. + Front-ends must adapt to different type for "cmpxchg". + Backends should be unaffected by default. llvm-svn: 210903		2014-06-13 14:24:07 +00:00
..
AArch64	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
ARM	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
CPP	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
Generic	Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.	2014-06-05 19:29:43 +00:00
Hexagon	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
Inputs
Mips	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
MSP430	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
NVPTX	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
PowerPC	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
R600	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
SPARC	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
SystemZ	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
Thumb	ARM: Fix fastcc calling convention for Thumb1	2014-06-13 08:33:03 +00:00
Thumb2	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
X86	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
XCore	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00