Duncan Sands 2a9c84481c Sometimes (rarely) nodes held in LegalizeTypes ... maps can be deleted. This happens when RAUW replaces a node N with another equivalent node E, deleting the first node. Solve this by adding (N, E) to ReplacedNodes, which is already used to remap nodes to replacements. This means that deleted nodes are being allowed in maps, which can be delicate: the memory may be reused for a new node which might get confused with the old deleted node pointer hanging around in the maps, so detect this and flush out maps if it occurs (ExpungeNode). The expunging operation is expensive, however it never occurs during a llvm-gcc bootstrap or anywhere in the nightly testsuite. It occurs three times in "make check": Alpha/illegal-element-type.ll, PowerPC/illegal-element-type.ll and X86/mmx-shift.ll. If expunging proves to be too expensive then there are other more complicated ways of solving the problem. In the normal case this patch adds the overhead of a few more map lookups, which is hopefully negligable. llvm-svn: 52214		2008-06-11 11:42:12 +00:00
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llvm	Sometimes (rarely) nodes held in LegalizeTypes	2008-06-11 11:42:12 +00:00
llvm-c	Remove a duplicative binding. Patch by Mahadevan R.	2008-05-19 05:47:10 +00:00