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path: root/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
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2010-06-23Revert r106263, "Fold the ShrinkDemandedOps pass into the regular ↵Daniel Dunbar
DAGCombiner pass,"... it was causing both 'file' (with clang) and 176.gcc (with llvm-gcc) to be miscompiled. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106634 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-23Some targets don't require the fencing MEMBARRIER instructions surroundingJim Grosbach
atomic intrinsics, either because the use locking instructions for the atomics, or because they perform the locking directly. Add support in the DAG combiner to fold away the fences. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106630 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-18Fold the ShrinkDemandedOps pass into the regular DAGCombiner pass,Dan Gohman
which is faster, simpler, and less surprising. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106263 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25Fix another variant of PR 7191. Also add a testcaseDale Johannesen
Mon Ping provided; unfortunately bugpoint failed to reduce it, but I think it's important to have a test for this in the suite. 8023512. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104624 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25Fix PR 7191. I have been unable to create a .ll file that fails, sorry.Dale Johannesen
(oye, a word which should be better known to people writing tree traversals, means grandchild.) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104619 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21Clean up extra whitespace.Bob Wilson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21Change CodeGen/ARM/2009-11-02-NegativeLane.ll to use 16-bit vector elementsBob Wilson
so that it will continue to test what it was meant to test when I commit a separate change for better support of BUILD_VECTOR and VECTOR_SHUFFLE for Neon. Fix a DAG combiner crash exposed by this test change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104380 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19Optimize away insertelement of an undef value. This shows up inBob Wilson
test/Codegen/ARM/reg_sequence.ll but it doesn't affect the generated code because the coalescer cleans it up. Radar 7998853. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104185 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19Intrinsics which do a vector compare (results are all zero or all ones) are ↵Evan Cheng
modeled as icmp / fcmp + sext. This is turned into a vsetcc by dag combine (yes, not a good long term solution). The targets can then isel the vsetcc to the appropriate instruction. The trouble arises when the result of a vector cmp + sext is then and'ed with all ones. Instcombine will turn it into a vector cmp + zext, dag combiner will miss turning it into a vsetcc and hell breaks loose after that. Teach dag combine to turn a vector cpm + zest into a vsetcc + and 1. This fixes rdar://7923010. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104094 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18Sink dag combine's post index load / store code that swap base ptr and index ↵Evan Cheng
into the target hook. Only the target knows whether the swap is safe. In Thumb2 mode, the offset must be an immediate. rdar://7998649 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104060 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18FIX PR7158. SimplifyVBinOp was asserting when it fails to constant fold (op ↵Evan Cheng
(build_vector), (build_vector)). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104004 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-10Be careful with operand promotion. For a binary operation, the source ↵Evan Cheng
operands may be the same. PR7018. rdar://7939869. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103419 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-30Apply a patch from Jan Sjodin to fix a compiler abort on vectorDan Gohman
comparisons sign-extended to a different bitwidth than the comparison operands. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102721 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-28Try operation promotion only if regular dag combine and target-specific ones ↵Evan Cheng
failed to do anything. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102492 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-27- When legal, promote a load to zextload rather than ext load.Evan Cheng
- Catch more further dag combine opportunities as result of operand promotion, e.g. (i32 anyext (i16 trunc (i32 x))) -> (i32 x) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102455 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24When a load operand is promoted to an extload, replace other uses with uses ↵Evan Cheng
of extload result truncated. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102236 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24Apply a fix for a vector setcc dagcombine from Jan Sjodin. NoDan Gohman
testcase yet, as the testcase now fails downstream. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102228 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-23Code refactoring.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102202 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-22- It's not safe to promote rotates (at least not trivially).Evan Cheng
- Some code refactoring. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-20The visitXOR method can return the same SDNode. If so, we don't want to deleteBill Wendling
it as it's not dead. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101855 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-19More progress on promoting i16 operations to i32 for x86. Work in progress.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101808 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-17More work to allow dag combiner to promote 16-bit ops to 32-bit.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101621 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16(i32 sext_in_reg (i32 aext (i16 x)), i16) -> (i32 sext x). No known test ↵Evan Cheng
case until -promote-16bit is enabled. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101551 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16Adding support for dag combiner to promote operations for profit. This ↵Evan Cheng
requires target specific queries. For example, x86 should promote i16 to i32 when it does not impact load folding. x86 support is off by default. It can be enabled with -promote-16bit. Work in progress. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101448 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15enhance the load/store narrowing optimization to handle aChris Lattner
tokenfactor in between the load/store. This allows us to optimize test7 into: _test7: ## @test7 ## BB#0: ## %entry movl (%rdx), %eax ## kill: SIL<def> ESI<kill> movb %sil, 5(%rdi) ret instead of: _test7: ## @test7 ## BB#0: ## %entry movl 4(%esp), %ecx movl $-65281, %eax ## imm = 0xFFFFFFFFFFFF00FF andl 4(%ecx), %eax movzbl 8(%esp), %edx shll $8, %edx addl %eax, %edx movl 12(%esp), %eax movl (%eax), %eax movl %edx, 4(%ecx) ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101355 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15teach codegen to turn trunc(zextload) into load when possible.Chris Lattner
This doesn't occur much at all, it only seems to formed in the case when the trunc optimization kicks in due to phase ordering. In that case it is saves a few bytes on x86-32. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101350 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15add a simple dag combine to replace trivial shl+lshr withChris Lattner
and. This happens with the store->load narrowing stuff. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101348 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15Implement rdar://7860110 (also in target/readme.txt) narrowingChris Lattner
a load/or/and/store sequence into a narrower store when it is safe. Daniel tells me that clang will start producing this sort of thing with bitfields, and this does trigger a few dozen times on 176.gcc produced by llvm-gcc even now. This compiles code like CodeGen/X86/2009-05-28-DAGCombineCrash.ll into: movl %eax, 36(%rdi) instead of: movl $4294967295, %eax ## imm = 0xFFFFFFFF andq 32(%rdi), %rax shlq $32, %rcx addq %rax, %rcx movq %rcx, 32(%rdi) and each of the testcases into a single store. Each of them used to compile into craziness like this: _test4: movl $65535, %eax ## imm = 0xFFFF andl (%rdi), %eax shll $16, %esi addl %eax, %esi movl %esi, (%rdi) ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101343 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15Add const qualifiers to CodeGen's use of LLVM IR constructs.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-12Remove unnecessary parens.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101010 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08Fix -Wsign-compare warning (issued by clang++).Ted Kremenek
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100799 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-07fix 80 col violation, patch by Alastair LynnChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100639 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-01Fix sdisel memcpy, memset, memmove lowering:Evan Cheng
1. Makes it possible to lower with floating point loads and stores. 2. Avoid unaligned loads / stores unless it's fast. 3. Fix some memcpy lowering logic bug related to when to optimize a load from constant string into a constant. 4. Adjust x86 memcpy lowering threshold to make it more sane. 5. Fix x86 target hook so it uses vector and floating point memory ops more effectively. rdar://7774704 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100090 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-10fix PR6533 by updating the br(xor) code to remember the caseChris Lattner
when it looked past a trunc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98203 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-10Fix another bitwidth calculation to handle vector types; based on aDan Gohman
patch by Micah Villmow for PR6572. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98188 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-04Fix more code to work properly with vector operands. Based onDan Gohman
a patch my Micah Villmow for PR6465. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97692 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03Use APInt instead of zext value.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97631 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03This test case:Bill Wendling
long test(long x) { return (x & 123124) | 3; } Currently compiles to: _test: orl $3, %edi movq %rdi, %rax andq $123127, %rax ret This is because instruction and DAG combiners canonicalize (or (and x, C), D) -> (and (or, D), (C | D)) However, this is only profitable if (C & D) != 0. It gets in the way of the 3-addressification because the input bits are known to be zero. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97616 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-02Fix several places to handle vector operands properly.Dan Gohman
Based on a patch by Micah Villmow for PR6438. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97538 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-27Re-apply 97040 with fix. This survives a ppc self-host llvm-gcc bootstrap.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97310 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-24Speculatively revert r97011, "Re-apply 96540 and 96556 with fixes.", again inDaniel Dunbar
the hopes of fixing PPC bootstrap. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97040 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-24Re-apply 96540 and 96556 with fixes.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97011 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-19Revert commits 96556 and 96640, because commit 96556 breaks theDuncan Sands
dragonegg self-host build. I reverted 96640 in order to revert 96556 (96640 goes on top of 96556), but it also looks like with both of them applied the breakage happens even earlier. The symptom of the 96556 miscompile is the following crash: llvm[3]: Compiling AlphaISelLowering.cpp for Release build cc1plus: /home/duncan/tmp/tmp/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4982: void llvm::SelectionDAG::ReplaceAllUsesWith(llvm::SDNode*, llvm::SDNode*, llvm::SelectionDAG::DAGUpdateListener*): Assertion `(!From->hasAnyUseOfValue(i) || From->getValueType(i) == To->getValueType(i)) && "Cannot use this version of ReplaceAllUsesWith!"' failed. Stack dump: 0. Running pass 'X86 DAG->DAG Instruction Selection' on function '@_ZN4llvm19AlphaTargetLowering14LowerOperationENS_7SDValueERNS_12SelectionDAGE' g++: Internal error: Aborted (program cc1plus) This occurs when building LLVM using LLVM built by LLVM (via dragonegg). Probably LLVM has miscompiled itself, though it may have miscompiled GCC and/or dragonegg itself: at this point of the self-host build, all of GCC, LLVM and dragonegg were built using LLVM. Unfortunately this kind of thing is extremely hard to debug, and while I did rummage around a bit I didn't find any smoking guns, aka obviously miscompiled code. Found by bisection. r96556 | evancheng | 2010-02-18 03:13:50 +0100 (Thu, 18 Feb 2010) | 5 lines Some dag combiner goodness: Transform br (xor (x, y)) -> br (x != y) Transform br (xor (xor (x,y), 1)) -> br (x == y) Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm" r96640 | evancheng | 2010-02-19 01:34:39 +0100 (Fri, 19 Feb 2010) | 16 lines Transform (xor (setcc), (setcc)) == / != 1 to (xor (setcc), (setcc)) != / == 1. e.g. On x86_64 %0 = icmp eq i32 %x, 0 %1 = icmp eq i32 %y, 0 %2 = xor i1 %1, %0 br i1 %2, label %bb, label %return => testl %edi, %edi sete %al testl %esi, %esi sete %cl cmpb %al, %cl je LBB1_2 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96672 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-18Some dag combiner goodness:Evan Cheng
Transform br (xor (x, y)) -> br (x != y) Transform br (xor (xor (x,y), 1)) -> br (x == y) Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm" git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96556 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-15Add non-temporal flags and remove an assumption of default arguments.David Greene
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96240 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10Fix "the the" and similar typos.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95781 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01Improve EXTRACT_VECTOR_ELT patch based on comments from DuncanMon P Wang
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95012 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01Fixed a couple of optimization with EXTRACT_VECTOR_ELT that assumes the resultMon P Wang
type is the same as the element type of the vector. EXTRACT_VECTOR_ELT can be used to extended the width of an integer type. This fixes a bug for Generic/vector-casts.ll on a ppc750. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94990 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26Implement cond ? -1 : 0 with sbb.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94490 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19Fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n)), to simplify some codeDan Gohman
that SCEVExpander can produce when running on behalf of LSR. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93949 91177308-0d34-0410-b5e6-96231b3b80d8