maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/lib/Transforms/Utils
History
Sanjay Patel c699a6117b fold: sqrt(x * x * y) -> fabs(x) * sqrt(y) 
If a square root call has an FP multiplication argument that can be reassociated,
then we can hoist a repeated factor out of the square root call and into a fabs().

In the simplest case, this:

   y = sqrt(x * x);

becomes this:

   y = fabs(x);

This patch relies on an earlier optimization in instcombine or reassociate to put the
multiplication tree into a canonical form, so we don't have to search over
every permutation of the multiplication tree.

Because there are no IR-level FastMathFlags for intrinsics (PR21290), we have to
use function-level attributes to do this optimization. This needs to be fixed
for both the intrinsics and in the backend.

Differential Revision: http://reviews.llvm.org/D5787

llvm-svn: 219944
 		2014-10-16 18:48:17 +00:00
..
ASanStackFrameLayout.cpp Revert "Introduce a string_ostream string builder facilty" 2014-06-26 22:52:05 +00:00
AddDiscriminators.cpp Use DILexicalBlockFile, rather than DILexicalBlock, to track discriminator changes to ensure discriminator changes don't introduce new DWARF DW_TAG_lexical_blocks. 2014-08-21 22:45:21 +00:00
BasicBlockUtils.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
BreakCriticalEdges.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
BuildLibCalls.cpp Simplify creation of a bunch of ArrayRefs by using None, makeArrayRef or just letting them be implicitly created. 2014-08-27 05:25:25 +00:00
BypassSlowDivision.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00
CMakeLists.txt Decouple llvm::SpecialCaseList text representation and its LLVM IR semantics. 2014-07-09 19:40:08 +00:00
CloneFunction.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
CloneModule.cpp C API: Add LLVMCloneModule() 2014-10-01 17:14:57 +00:00
CmpInstAnalysis.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00
CodeExtractor.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
CtorUtils.cpp GlobalOpt: Preserve comdats of unoptimized initializers 2014-09-23 22:33:01 +00:00
DemoteRegToStack.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00
FlattenCFG.cpp utils: Fix segfault in flattencfg 2014-08-13 20:31:53 +00:00
GlobalStatus.cpp Remove dangling initializers in GlobalDCE 2014-08-25 17:51:14 +00:00
InlineFunction.cpp Preserve non-byval pointer alignment attributes using @llvm.assume when inlining 2014-10-15 23:44:41 +00:00
InstructionNamer.cpp [C++11] Add 'override' keyword to virtual methods that override their base class. 2014-03-05 09:10:37 +00:00
IntegerDivision.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:55:47 +00:00
LCSSA.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:55:47 +00:00
LLVMBuild.txt
…
Local.cpp DIBuilder: Encapsulate DIExpression's element type 2014-10-01 20:26:08 +00:00
LoopSimplify.cpp Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.) 2014-09-07 18:57:58 +00:00
LoopUnroll.cpp LoopUnroll: Create sub-loops in LoopInfo 2014-10-07 21:19:00 +00:00
LoopUnrollRuntime.cpp Use a loop to simplify the runtime unrolling prologue. 2014-09-29 11:15:00 +00:00
LowerExpectIntrinsic.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:55:47 +00:00
LowerInvoke.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:55:47 +00:00
LowerSwitch.cpp Fixup PHIs in LowerSwitch when a Leaf node is not emitted. 2014-07-11 10:34:36 +00:00
Makefile
…
Mem2Reg.cpp Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.) 2014-09-07 18:57:58 +00:00
MetaRenamer.cpp [C++11] Add 'override' keyword to virtual methods that override their base class. 2014-03-05 09:10:37 +00:00
ModuleUtils.cpp Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size. 2014-08-21 05:55:13 +00:00
PromoteMemoryToRegister.cpp Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.) 2014-09-07 18:57:58 +00:00
SSAUpdater.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
SimplifyCFG.cpp Switch to select optimization for two-case switches 2014-10-14 01:58:26 +00:00
SimplifyIndVar.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00
SimplifyInstructions.cpp Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.) 2014-09-07 18:57:58 +00:00
SimplifyLibCalls.cpp fold: sqrt(x * x * y) -> fabs(x) * sqrt(y) 2014-10-16 18:48:17 +00:00
UnifyFunctionExitNodes.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00
Utils.cpp Pass to emit DWARF path discriminators. 2014-03-03 20:06:11 +00:00
ValueMapper.cpp [C++] Use 'nullptr'. Transforms edition. 2014-04-25 05:29:35 +00:00