Owen Anderson 7a0201c6a6 Remove an InstCombine that transformed patterns like (x * uitofp i1 y) to (select y, x, 0.0) when the multiply has fast math flags set. ... While this might seem like an obvious canonicalization, there is one subtle problem with it. The result of the original expression is undef when x is NaN (remember, fast math flags), but the result of the select is always defined when x is NaN. This means that the new expression is strictly more defined than the original one. One unfortunate consequence of this is that the transform is not reversible! It's always legal to make increase the defined-ness of an expression, but it's not legal to reduce it. Thus, targets that prefer the original form of the expression cannot reverse the transform to recover it. Another way to think of it is that the transform has lost source-level information (the fast math flags), which is undesirable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215825 91177308-0d34-0410-b5e6-96231b3b80d8		2014-08-17 03:51:29 +00:00
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Hello
InstCombine	Remove an InstCombine that transformed patterns like (x * uitofp i1 y) to (select y, x, 0.0) when the multiply has fast math flags set.	2014-08-17 03:51:29 +00:00
Instrumentation
IPO
ObjCARC
Scalar	Introduce a helper to combine instruction metadata.	2014-08-15 15:46:38 +00:00
Utils	Introduce a helper to combine instruction metadata.	2014-08-15 15:46:38 +00:00
Vectorize	Introduce a helper to combine instruction metadata.	2014-08-15 15:46:38 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile