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path: root/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
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2009-09-10Don't swap the operands of a subtraction when trying to create aBob Wilson
post-decrement load/store. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81464 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-06Remove some unused variables and methods warned about byDuncan Sands
icc (#177, partial). Patch by Erick Tryzelaar. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81106 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23remove a few DOUTs here and there.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79832 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23Add check for completeness. Note that this doesn't actually have any Eli Friedman
effect with the way the current code is structured. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79792 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-19PR4737: Fix a nasty bug in load narrowing with non-power-of-two types.Eli Friedman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79415 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-12Add contexts to some of the MVT APIs. No functionality change yet, just the ↵Owen Anderson
infrastructure work needed to get the contexts to where they need to be first. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78759 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-11Split EVT into MVT and EVT, the former representing _just_ a primitive type, ↵Owen Anderson
while the latter is capable of representing either a primitive or an extended type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78713 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10Fix a bug in the DAGCombiner's handling of multiple linkedDan Gohman
MERGE_VALUES nodes. Replacing the result values with the operands in one MERGE_VALUES node may cause another MERGE_VALUES node be CSE'd with the first one, and bring its uses along, so that the first one isn't dead, as this code expects. Fix this by iterating until the node is really dead. This fixes PR4699. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78619 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10Fix a bug where DAGCombine was producing an illegal ConstantFPDan Gohman
node after legalize, and remove the workaround code from the ARM backend. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78615 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10Rename MVT to EVT, in preparation for splitting SimpleValueType out into its ↵Owen Anderson
own struct type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78610 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10Make this comment more closely reflect the code.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78569 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-08Don't build illegal ops in DAGCombiner::SimplifyBinOpWithSameOpcodeHands().Jakob Stoklund Olesen
Blackfin supports and/or/xor on i32 but not on i16. Teach DAGCombiner::SimplifyBinOpWithSameOpcodeHands to not produce illegal nodes after legalize ops. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78497 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-06Fix a few places in DAGCombiner that were creating all-ones-bitsDan Gohman
and high-bits values in ways that weren't correct for integer types wider than 64 bits. This fixes a miscompile in PPMacroExpansion.cpp in clang on x86-64. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78295 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02Avoid forming a SELECT_CC in a type that the target doesn'tDan Gohman
support. This isn't immediately interesting, because Legalize ends up lowering SELECT_CC if the target doesn't support it, but this simplifies the process. Also, if the SELECT_CC would be expanded in Legalize, it can potentially end up with two copies of the condition expression. By leaving it as SELECT+SETCC, the SELECT can be expanded into two SELECTs that use a single SETCC. The two comparisons are usually CSE'd, but depending on when various expressions get legalized, the comparison expression could involve calls to library functions, such that the comparison expression may not be able to be CSE'd. This will be needed by a future patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77896 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-29Move types back to the 2.5 API.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77516 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-28Change ConstantArray to 2.5 API.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77347 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24Add support for promoting SETCC operations.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76987 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21Fix a dagga combiner bug: avoid creating illegal constant.Evan Cheng
Is this really a winning transformation? fold (shl (srl x, c1), c2) -> (shl (and x, (shl -1, c1)), (sub c2, c1)) or (srl (and x, (shl -1, c1)), (sub c1, c2)) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76535 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-15Move a few more convenience factory functions from Constant to LLVMContext.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75840 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14llvm_unreachable->llvm_unreachable(0), LLVM_UNREACHABLE->llvm_unreachable.Torok Edwin
This adds location info for all llvm_unreachable calls (which is a macro now) in !NDEBUG builds. In NDEBUG builds location info and the message is off (it only prints "UREACHABLE executed"). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75640 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-11assert(0) -> LLVM_UNREACHABLE.Torok Edwin
Make llvm_unreachable take an optional string, thus moving the cerr<< out of line. LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for NDEBUG builds. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75379 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-11Convert more assert(0)+abort() -> LLVM_UNREACHABLE,Torok Edwin
and abort()/exit() -> llvm_report_error(). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75363 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-09Thread LLVMContext through MVT and related parts of SDISel.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75153 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-08dag combine sext(setcc) -> vsetcc before legalize. To make this safe,Chris Lattner
VSETCC must define all bits, which is different than it was documented to before. Since all targets that implement VSETCC already have this behavior, and we don't optimize based on this, just change the documentation. We now get nice code for vec_compare.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74978 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-05Adapt the x86 build_vector dagcombine to the current state of the legalizer.Nate Begeman
build vectors with i64 elements will only appear on 32b x86 before legalize. Since vector widening occurs during legalize, and produces i64 build_vector elements, the dag combiner is never run on these before legalize splits them into 32b elements. Teach the build_vector dag combine in x86 back end to recognize consecutive loads producing the low part of the vector. Convert the two uses of TLI's consecutive load recognizer to pass LoadSDNodes since that was required implicitly. Add a testcase for the transform. Old: subl $28, %esp movl 32(%esp), %eax movl 4(%eax), %ecx movl %ecx, 4(%esp) movl (%eax), %eax movl %eax, (%esp) movaps (%esp), %xmm0 pmovzxwd %xmm0, %xmm0 movl 36(%esp), %eax movaps %xmm0, (%eax) addl $28, %esp ret New: movl 4(%esp), %eax pmovzxwd (%eax), %xmm0 movl 8(%esp), %eax movaps %xmm0, (%eax) ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72957 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04Don't do the X * 0.0 -> 0.0 transformation in instcombine, becauseDan Gohman
instcombine doesn't know when it's safe. To partially compensate for this, introduce new code to do this transformation in dagcombine, which can use UnsafeFPMath. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72872 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-02Revert 72707 and 72709, for the moment.Dale Johannesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72712 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-01Make the implicit inputs and outputs of target-independentDale Johannesen
ADDC/ADDE use MVT::i1 (later, whatever it gets legalized to) instead of MVT::Flag. Remove CARRY_FALSE in favor of 0; adjust all target-independent code to use this format. Most targets will still produce a Flag-setting target-dependent version when selection is done. X86 is converted to use i32 instead, which means TableGen needs to produce different code in xxxGenDAGISel.inc. This keys off the new supportsHasI1 bit in xxxInstrInfo, currently set only for X86; in principle this is temporary and should go away when all other targets have been converted. All relevant X86 instruction patterns are modified to represent setting and using EFLAGS explicitly. The same can be done on other targets. The immediate behavior change is that an ADC/ADD pair are no longer tightly coupled in the X86 scheduler; they can be separated by instructions that don't clobber the flags (MOV). I will soon add some peephole optimizations based on using other instructions that set the flags to feed into ADC. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72707 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-28Do not try to create a MVT type of width 0.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72557 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-28Incorporate patch feedbacks.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72533 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-28Added optimization that narrow load / op / store and the 'op' is a bit ↵Evan Cheng
twiddling instruction and its second operand is an immediate. If bits that are touched by 'op' can be done with a narrower instruction, reduce the width of the load and store as well. This happens a lot with bitfield manipulation code. e.g. orl $65536, 8(%rax) => orb $1, 10(%rax) Since narrowing is not always a win, e.g. i32 -> i16 is a loss on x86, dag combiner consults with the target before performing the optimization. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72507 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-23Fix PR4254.Torok Edwin
The DAGCombiner created a negative shiftamount, stored in an unsigned variable. Later the optimizer eliminated the shift entirely as being undefined. Example: (srl (shl X, 56) 48). ShiftAmt is 4294967288. Fix it by checking that the shiftamount is positive, and storing in a signed variable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72331 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18Silence Release-Asserts warnings.Daniel Dunbar
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72011 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-09Rename PaddedSize to AllocSize, in the hope that thisDuncan Sands
will make it more obvious what it represents, and stop it being confused with the StoreSize. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71349 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-06Do not use register as base ptr of pre- and post- inc/dec load / store nodes.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71098 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29Instead of passing in an unsigned value for the optimization level, use an enum,Bill Wendling
which better identifies what the optimization is doing. And is more flexible for future uses. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70440 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29Implement review feedback for vector shuffle work.Nate Begeman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70372 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29Second attempt:Bill Wendling
Massive check in. This changes the "-fast" flag to "-O#" in llc. If you want to use the old behavior, the flag is -O0. This change allows for finer-grained control over which optimizations are run at different -O levels. Most of this work was pretty mechanical. The majority of the fixes came from verifying that a "fast" variable wasn't used anymore. The JIT still uses a "Fast" flag. I'll change the JIT with a follow-up patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70343 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28r70270 isn't ready yet. Back this out. Sorry for the noise.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70275 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28Massive check in. This changes the "-fast" flag to "-O#" in llc. If you want toBill Wendling
use the old behavior, the flag is -O0. This change allows for finer-grained control over which optimizations are run at different -O levels. Most of this work was pretty mechanical. The majority of the fixes came from verifying that a "fast" variable wasn't used anymore. The JIT still uses a "Fast" flag. I'm not 100% sure if it's necessary to change it there... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70270 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-272nd attempt, fixing SSE4.1 issues and implementing feedback from duncan.Nate Begeman
PR2957 ISD::VECTOR_SHUFFLE now stores an array of integers representing the shuffle mask internal to the node, rather than taking a BUILD_VECTOR of ConstantSDNodes as the shuffle mask. A value of -1 represents UNDEF. In addition to eliminating the creation of illegal BUILD_VECTORS just to represent shuffle masks, we are better about canonicalizing the shuffle mask, resulting in substantially better code for some classes of shuffles. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70225 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-27When transforming sext(trunc(load(x))) into sext(smaller load(x)),Dan Gohman
the trunc is directly replaced with the smaller load, so don't try to create a new sext node. This fixes PR4050. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70179 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-25Add a top-level comment about DAGCombiner's role in the compiler.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70052 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-24Revert 69952. Causes testsuite failures on linux x86-64.Rafael Espindola
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69967 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-24PR2957Nate Begeman
ISD::VECTOR_SHUFFLE now stores an array of integers representing the shuffle mask internal to the node, rather than taking a BUILD_VECTOR of ConstantSDNodes as the shuffle mask. A value of -1 represents UNDEF. In addition to eliminating the creation of illegal BUILD_VECTORS just to represent shuffle masks, we are better about canonicalizing the shuffle mask, resulting in substantially better code for some classes of shuffles. A clean up of x86 shuffle code, and some canonicalizing in DAGCombiner is next. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69952 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-20Revise my previous change 68996 as suggested by Duncan.Bob Wilson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69607 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-18Don't try to make BUILD_VECTOR operands have the sameDuncan Sands
type as the vector element type: allow them to be of a wider integer type than the element type all the way through the system, and not just as far as LegalizeDAG. This should be safe because it used to be this way (the old type legalizer would produce such nodes), so backends should be able to handle it. In fact only targets which have legal vector types with an illegal promoted element type will ever see this (eg: <4 x i16> on ppc). This fixes a regression with the new type legalizer (vec_splat.ll). Also, treat SCALAR_TO_VECTOR the same as BUILD_VECTOR. After all, it is just a special case of BUILD_VECTOR. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69467 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-13Change SelectionDAG type legalization to allow BUILD_VECTOR operands to beBob Wilson
promoted to legal types without changing the type of the vector. This is following a suggestion from Duncan (http://lists.cs.uiuc.edu/pipermail/llvmdev/2009-February/019923.html). The transformation that used to be done during type legalization is now postponed to DAG legalization. This allows the BUILD_VECTORs to be optimized and potentially handled specially by target-specific code. It turns out that this is also consistent with an optimization done by the DAG combiner: a BUILD_VECTOR and INSERT_VECTOR_ELT may be combined by replacing one of the BUILD_VECTOR operands with the newly inserted element; but INSERT_VECTOR_ELT allows its scalar operand to be larger than the element type, with any extra high bits being implicitly truncated. The result is a BUILD_VECTOR where one of the operands has a type larger the the vector element type. Any code that operates on BUILD_VECTORs may now need to be aware of the potential type discrepancy between the vector element type and the BUILD_VECTOR operands. This patch updates all of the places that I could find to handle that case. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68996 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-09Generalize ExtendUsesToFormExtLoad to be usable for ANY_EXTEND,Dan Gohman
in addition to ZERO_EXTEND and SIGN_EXTEND. Fix a bug in the way it checked for live-out values, and simplify the way it find users by using SDNode::use_iterator's (relatively) new features. Also, make it slightly more permissive on targets with free truncates. In SelectionDAGBuild, avoid creating ANY_EXTEND nodes that are larger than necessary. If the target's SwitchAmountTy has enough bits, use it. This exposes the truncate to optimization early, enabling more optimizations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68670 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-08Implement support for using modeling implicit-zero-extension on x86-64Dan Gohman
with SUBREG_TO_REG, teach SimpleRegisterCoalescing to coalesce SUBREG_TO_REG instructions (which are similar to INSERT_SUBREG instructions), and teach the DAGCombiner to take advantage of this on targets which support it. This eliminates many redundant zero-extension operations on x86-64. This adds a new TargetLowering hook, isZExtFree. It's similar to isTruncateFree, except it only applies to actual definitions, and not no-op truncates which may not zero the high bits. Also, this adds a new optimization to SimplifyDemandedBits: transform operations like x+y into (zext (add (trunc x), (trunc y))) on targets where all the casts are no-ops. In contexts where the high part of the add is explicitly masked off, this allows the mask operation to be eliminated. Fix the DAGCombiner to avoid undoing these transformations to eliminate casts on targets where the casts are no-ops. Also, this adds a new two-address lowering heuristic. Since two-address lowering runs before coalescing, it helps to be able to look through copies when deciding whether commuting and/or three-address conversion are profitable. Also, fix a bug in LiveInterval::MergeInClobberRanges. It didn't handle the case that a clobber range extended both before and beyond an existing live range. In that case, multiple live ranges need to be added. This was exposed by the new subreg coalescing code. Remove 2008-05-06-SpillerBug.ll. It was bugpoint-reduced, and the spiller behavior it was looking for no longer occurrs with the new instruction selection. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68576 91177308-0d34-0410-b5e6-96231b3b80d8
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