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path: root/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
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* Rename TargetFrameInfo into TargetFrameLowering. Also, put couple of FIXMEs ↵Anton Korobeynikov2011-01-101-1/+0
| | | | | | and fixes here and there. llvm-svn: 123170
* DAGCombine add (sext i1), X into sub X, (zext i1) if sext from i1 is ↵Benjamin Kramer2010-12-221-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | illegal. The latter usually compiles into smaller code. example code: unsigned foo(unsigned x, unsigned y) { if (x != 0) y--; return y; } before: _foo: ## @foo cmpl $1, 4(%esp) ## encoding: [0x83,0x7c,0x24,0x04,0x01] sbbl %eax, %eax ## encoding: [0x19,0xc0] notl %eax ## encoding: [0xf7,0xd0] addl 8(%esp), %eax ## encoding: [0x03,0x44,0x24,0x08] ret ## encoding: [0xc3] after: _foo: ## @foo cmpl $1, 4(%esp) ## encoding: [0x83,0x7c,0x24,0x04,0x01] movl 8(%esp), %eax ## encoding: [0x8b,0x44,0x24,0x08] adcl $-1, %eax ## encoding: [0x83,0xd0,0xff] ret ## encoding: [0xc3] llvm-svn: 122455
* Fix a bug in ReduceLoadWidth that wasn't handling extendingChris Lattner2010-12-221-1/+4
| | | | | | | | | | | | | | | | | | | | | loads properly. We miscompiled the testcase into: _test: ## @test movl $128, (%rdi) movzbl 1(%rdi), %eax ret Now we get a proper: _test: ## @test movl $128, (%rdi) movsbl (%rdi), %eax movzbl %ah, %eax ret This fixes PR8757. llvm-svn: 122392
* more cleanups, move a check for "roundedness" earlier to rejectChris Lattner2010-12-221-14/+20
| | | | | | unhanded cases faster and simplify code. llvm-svn: 122391
* reduce indentation and improve comments, no functionality change.Chris Lattner2010-12-221-51/+53
| | | | llvm-svn: 122389
* Reapply 122353-122355 with fixes. 122354 was wrong;Dale Johannesen2010-12-211-4/+31
| | | | | | | | the shift type was needed one place, the shift count type another. The transform in 123555 had the same problem. llvm-svn: 122366
* Revert 122353-122355 for the moment, they broke stuff.Dale Johannesen2010-12-211-29/+3
| | | | llvm-svn: 122360
* Add a new transform to DAGCombiner.Dale Johannesen2010-12-211-0/+26
| | | | llvm-svn: 122355
* Get the type of a shift from the shift, not from its shiftDale Johannesen2010-12-211-1/+1
| | | | | | | | count operand. These should be the same but apparently are not always, and this is cleaner anyway. This improves the code in an existing test. llvm-svn: 122354
* Shift by the word size is invalid IR; don't create it.Dale Johannesen2010-12-211-2/+2
| | | | llvm-svn: 122353
* fix some typosChris Lattner2010-12-211-2/+1
| | | | llvm-svn: 122349
* rename MVT::Flag to MVT::Glue. "Flag" is a terrible name forChris Lattner2010-12-211-3/+3
| | | | | | | something that just glues two nodes together, even if it is sometimes used for flags. llvm-svn: 122310
* Cosmetic changes.Dale Johannesen2010-12-201-2/+2
| | | | llvm-svn: 122259
* Fix a DAGCombiner crash when folding binary vector operations with constantBob Wilson2010-12-171-16/+9
| | | | | | | BUILD_VECTOR operands where the element type is not legal. I had previously changed this code to insert TRUNCATE operations, but that was just wrong. llvm-svn: 122102
* Add a transform to DAG Combiner. This improves theDale Johannesen2010-12-171-0/+20
| | | | | | | code for the case where 32-bit divide by constant is turned into 64-bit multiply by constant. 8771012. llvm-svn: 122090
* take care of some todos, transforming [us]mul_lohi into Chris Lattner2010-12-151-2/+46
| | | | | | a wider mul if the wider mul is legal. llvm-svn: 121848
* when transforming a MULHS into a wider MUL, there is no need to SRA theChris Lattner2010-12-151-1/+1
| | | | | | result, the top bits are truncated off anyway, just use SRL. llvm-svn: 121846
* Add a couple dag combines to transform mulhi/mullo into a wider multiplyChris Lattner2010-12-131-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | when the wider type is legal. This allows us to compile: define zeroext i16 @test1(i16 zeroext %x) nounwind { entry: %div = udiv i16 %x, 33 ret i16 %div } into: test1: # @test1 movzwl 4(%esp), %eax imull $63551, %eax, %eax # imm = 0xF83F shrl $21, %eax ret instead of: test1: # @test1 movw $-1985, %ax # imm = 0xFFFFFFFFFFFFF83F mulw 4(%esp) andl $65504, %edx # imm = 0xFFE0 movl %edx, %eax shrl $5, %eax ret Implementing rdar://8760399 and example #4 from: http://blog.regehr.org/archives/320 We should implement the same thing for [su]mul_hilo, but I don't have immediate plans to do this. llvm-svn: 121696
* 80-col fixups.Eric Christopher2010-12-091-9/+15
| | | | llvm-svn: 121356
* PR5207: Change APInt methods trunc(), sext(), zext(), sextOrTrunc() andJay Foad2010-12-071-11/+11
| | | | | | | | zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method trunc(), to be const and to return a new value instead of modifying the object in place. llvm-svn: 121120
* Fix a comment typo.Bob Wilson2010-11-281-1/+1
| | | | llvm-svn: 120235
* Renaming ISD::BIT_CONVERT to ISD::BITCAST to better reflect the LLVM IR concept.Wesley Peck2010-11-231-105/+105
| | | | llvm-svn: 119990
* Fix thinko: we must turn select(anyext, sext) into sext(select)Duncan Sands2010-11-181-1/+2
| | | | | | not anyext(select). Spotted by Frits van Bommel. llvm-svn: 119739
* The DAGCombiner was threading select over pairs of extending loads evenDuncan Sands2010-11-181-0/+5
| | | | | | | | | | if the extension types were not the same. The result was that if you fed a select with sext and zext loads, as in the testcase, then it would get turned into a zext (or sext) of the select, which is wrong in the cases when it should have been an sext (resp. zext). Reported and diagnosed by Sebastien Deldon. llvm-svn: 119728
* Fix DAGCombiner to avoid folding a sext-in-reg or similar through a shlDan Gohman2010-11-091-0/+1
| | | | | | in order to fold it into a load. llvm-svn: 118471
* Just return undef for invalid masks or elts, and since we're doing that,Eric Christopher2010-11-031-5/+6
| | | | | | just do it earlier too. llvm-svn: 118195
* If we have an undef mask our Elt will be -1 for our access, handleEric Christopher2010-11-031-3/+7
| | | | | | | | this by using an undef as a pointer. Fixes rdar://8625016 llvm-svn: 118164
* Fix DAGCombiner to avoid going into an infinite loop when itDan Gohman2010-11-031-1/+36
| | | | | | | encounters (and:i64 (shl:i64 (load:i64), 1), 0xffffffff). This fixes rdar://8606584. llvm-svn: 118143
* Remove DAG combiner patch to fold vector splats. Instcombiner does it now.Bob Wilson2010-10-291-5/+0
| | | | llvm-svn: 117720
* Teach the DAG combiner to fold a splat of a splat. Radar 8597790.Bob Wilson2010-10-281-24/+28
| | | | | | Also do some minor refactoring to reduce indentation. llvm-svn: 117558
* Make CodeGen TBAA-aware.Dan Gohman2010-10-201-8/+21
| | | | llvm-svn: 116890
* This DAG combine BRCOND transformation can look pass truncate of the operand:Evan Cheng2010-10-041-13/+18
| | | | | | | | | | | | | | | | | | | | // %a = ... // %b = and i32 %a, 2 // %c = srl i32 %b, 1 // brcond i32 %c ... // // into // // %a = ... // %b = and i32 %a, 2 // %c = setcc eq %b, 0 // brcond %c ... Make sure it restores local variable N1, which corresponds to the condition operand if it fails to match. This apparently breaks TCE but since that backend isn't in the tree I don't have a test for it. llvm-svn: 115571
* fix rdar://8494845 + PR8244 - a miscompile exposed by my patch in r101350Chris Lattner2010-10-011-0/+9
| | | | llvm-svn: 115294
* A select between a constant and zero, when fed by a bit test, can be efficientlyOwen Anderson2010-09-221-0/+29
| | | | | | | lowered using a series of shifts. Fixes <rdar://problem/8285015>. llvm-svn: 114599
* Reimplement r114460 in target-independent DAGCombine rather than ↵Owen Anderson2010-09-211-0/+14
| | | | | | | | | target-dependent, by using the predicate to discover the number of sign bits. Enhance X86's target lowering to provide a useful response to this query. llvm-svn: 114473
* update a bunch of code to use the MachinePointerInfo version of getStore.Chris Lattner2010-09-211-14/+8
| | | | llvm-svn: 114461
* eliminate an old SelectionDAG::getTruncStore method, propagatingChris Lattner2010-09-211-7/+4
| | | | | | MachinePointerInfo around more. llvm-svn: 114452
* propagate MachinePointerInfo through various uses of the oldChris Lattner2010-09-211-28/+22
| | | | | | SelectionDAG::getExtLoad overload, and eliminate it. llvm-svn: 114446
* convert dagcombine off the old form of getLoad. This fixes several bugs Chris Lattner2010-09-211-16/+18
| | | | | | with SVOffset computation. llvm-svn: 114442
* simplify DAGCombiner::SimplifySelectOps step #2/2.Chris Lattner2010-09-211-55/+53
| | | | llvm-svn: 114437
* substantially reduce indentation and simplify DAGCombiner::SimplifySelectOps.Chris Lattner2010-09-211-85/+76
| | | | | | no functionality change (step #1) llvm-svn: 114436
* a few more trivial updates. This fixes PerformInsertVectorEltInMemory to notChris Lattner2010-09-211-1/+1
| | | | | | | pass a completely incorrect SrcValue, which would result in a miscompile with combiner-aa. llvm-svn: 114411
* When TCO is turned on, it is possible to end up with aliasing FrameIndex's. ↵Owen Anderson2010-09-201-2/+13
| | | | | | | | | | | | Therefore, CombinerAA cannot assume that different FrameIndex's never alias, but can instead use MachineFrameInfo to get the actual offsets of these slots and check for actual aliasing. This fixes CodeGen/X86/2010-02-19-TailCallRetAddrBug.ll and CodeGen/X86/tailcallstack64.ll when CombinerAA is enabled, modulo a different register allocation sequence. llvm-svn: 114348
* Revert r114312 while I sort out some issues.Owen Anderson2010-09-191-1/+1
| | | | llvm-svn: 114313
* Tentatively enabled DAGCombiner Alias Analysis by default. As far as I know,Owen Anderson2010-09-191-1/+1
| | | | | | | r114268 fixed the last of the blockers to enabling it. I will be monitoring for failures. llvm-svn: 114312
* Don't narrow the load and store in a load+twiddle+store sequence unlessDan Gohman2010-09-021-1/+2
| | | | | | | | | | there are clearly no stores between the load and the store. This fixes this miscompile reported as PR7833. This breaks the test/CodeGen/X86/narrow_op-2.ll optimization, which is safe, but awkward to prove safe. Move it to X86's README.txt. llvm-svn: 112861
* Fix a crash in the dag combiner caused by ↵Nate Begeman2010-07-271-2/+10
| | | | | | | | ConstantFoldBIT_CONVERTofBUILD_VECTOR calling itself recursively and returning a SCALAR_TO_VECTOR node, but assuming the input was always a BUILD_VECTOR. llvm-svn: 109519
* Remove r108639 now that it is handled by InstCombine instead.Owen Anderson2010-07-191-13/+0
| | | | llvm-svn: 108688
* Add a DAGCombine xform to fold away redundant float->double->float ↵Owen Anderson2010-07-181-0/+13
| | | | | | | | | | conversions around sqrt instructions. I am assured by people more knowledgeable than me that there are no rounding issues in eliminating this. This fixed <rdar://problem/8197504>. llvm-svn: 108639
* Convert some tab stops into spaces.Duncan Sands2010-07-121-28/+28
| | | | llvm-svn: 108130
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