Jakob Stoklund Olesen 72847f3057 Reapply r155136 after fixing PR12599. ... Original commit message: Defer some shl transforms to DAGCombine. The shl instruction is used to represent multiplication by a constant power of two as well as bitwise left shifts. Some InstCombine transformations would turn an shl instruction into a bit mask operation, making it difficult for later analysis passes to recognize the constsnt multiplication. Disable those shl transformations, deferring them to DAGCombine time. An 'shl X, C' instruction is now treated mostly the same was as 'mul X, C'. These transformations are deferred: (X >>? C) << C --> X & (-1 << C) (When X >> C has multiple uses) (X >>? C1) << C2 --> X << (C2-C1) & (-1 << C2) (When C2 > C1) (X >>? C1) << C2 --> X >>? (C1-C2) & (-1 << C2) (When C1 > C2) The corresponding exact transformations are preserved, just like div-exact + mul: (X >>?,exact C) << C --> X (X >>?,exact C1) << C2 --> X << (C2-C1) (X >>?,exact C1) << C2 --> X >>?,exact (C1-C2) The disabled transformations could also prevent the instruction selector from recognizing rotate patterns in hash functions and cryptographic primitives. I have a test case for that, but it is too fragile. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155362 91177308-0d34-0410-b5e6-96231b3b80d8		2012-04-23 17:39:52 +00:00
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Analysis	Revert "SCEV: When expanding a GEP the final addition to the base pointer has NUW but not NSW."	2012-04-17 06:33:57 +00:00
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CodeGen	cleaned line endings in the newly added test file	2012-04-22 13:22:48 +00:00
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Linker	Remove llvm-ld and llvm-stub (which is only used by llvm-ld).	2012-04-19 19:27:54 +00:00
MC	ARM: Update NEON assembly two-operand aliases.	2012-04-20 18:12:54 +00:00
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Transforms	Reapply r155136 after fixing PR12599.	2012-04-23 17:39:52 +00:00
Unit
Verifier	Remove support for the special 'fast' value for fpmath accuracy for the moment.	2012-04-16 19:39:33 +00:00
YAMLParser
CMakeLists.txt	Removes json-bench from the test dependencies.	2012-04-20 13:45:49 +00:00
lit.cfg	Remove llvm-ld and llvm-stub (which is only used by llvm-ld).	2012-04-19 19:27:54 +00:00
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