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2012-07-27fix infinite loop in instcombine in the presence of a (malformed) ↵Nuno Lopes
self-referencing select inst. This can happen as long as the instruction is not reachable. Instcombine does generate these unreachable malformed selects when doing RAUW git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160874 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-26Simplify demanded bits of select sources where the condition is a constant ↵Pete Cooper
vector git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160835 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-26Teach SimplifyDemandedBits how to look through fpext and fptrunc to simplify ↵Pete Cooper
their operand git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160823 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-25make all Emit*() functions consult the TargetLibraryInfo information before ↵Nuno Lopes
creating a call to a library function. Update all clients to pass the TLI information around. Previous draft reviewed by Eli. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160733 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-19Remove tabs.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160477 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-17Back out r160101 and instead implement a dag combine to recover from ↵Evan Cheng
instcombine transformation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160387 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-12Instcombine was transforming:Evan Cheng
%shr = lshr i64 %key, 3 %0 = load i64* %val, align 8 %sub = add i64 %0, -1 %and = and i64 %sub, %shr ret i64 %and to: %shr = lshr i64 %key, 3 %0 = load i64* %val, align 8 %sub = add i64 %0, 2305843009213693951 %and = and i64 %sub, %shr ret i64 %and The demanded bit optimization is actually a pessimization because add -1 would be codegen'ed as a sub 1. Teach the demanded constant shrinking optimization to check for negated constant to make sure it is actually reducing the width of the constant. rdar://11793464 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160101 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-09instcombine: merge the functions that remove dead allocas and dead ↵Nuno Lopes
mallocs/callocs/... This patch removes ~70 lines in InstCombineLoadStoreAlloca.cpp and makes both functions a bit more aggressive than before :) In theory, we can be more aggressive when removing an alloca than a malloc, because an alloca pointer should never escape, but we are not taking advantage of this anyway git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159952 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-06teach instcombine to remove allocated buffers even if there are stores, ↵Nuno Lopes
memcpy/memmove/memset, and objectsize users. This means we can do cheap DSE for heap memory. Nothing is done if the pointer excapes or has a load. The churn in the tests is mostly due to objectsize, since we want to make sure we don't delete the malloc call before evaluating the objectsize (otherwise it becomes -1/0) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159876 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-29Move llvm/Support/IRBuilder.h -> llvm/IRBuilder.hChandler Carruth
This was always part of the VMCore library out of necessity -- it deals entirely in the IR. The .cpp file in fact was already part of the VMCore library. This is just a mechanical move. I've tried to go through and re-apply the coding standard's preferred header sort, but at 40-ish files, I may have gotten some wrong. Please let me know if so. I'll be committing the corresponding updates to Clang and Polly, and Duncan has DragonEgg. Thanks to Bill and Eric for giving the green light for this bit of cleanup. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159421 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-28make instcombine produce calls to llvm.donothing instead of a random intrinsicNuno Lopes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159384 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-26Remove a instcombine transform that (no longer?) makes sense:Evan Cheng
// C - zext(bool) -> bool ? C - 1 : C if (ZExtInst *ZI = dyn_cast<ZExtInst>(Op1)) if (ZI->getSrcTy()->isIntegerTy(1)) return SelectInst::Create(ZI->getOperand(0), SubOne(C), C); This ends up forming sext i1 instructions that codegen to terrible code. e.g. int blah(_Bool x, _Bool y) { return (x - y) + 1; } => movzbl %dil, %eax movzbl %sil, %ecx shll $31, %ecx sarl $31, %ecx leal 1(%rax,%rcx), %eax ret Without the rule, llvm now generates: movzbl %sil, %ecx movzbl %dil, %eax incl %eax subl %ecx, %eax ret It also helps with ARM (and pretty much any target that doesn't have a sext i1 :-). The transformation was done as part of Eli's r75531. He has given the ok to remove it. rdar://11748024 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159230 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-26Replacing zero-sized alloca's with a null pointer is too aggressive, insteadDuncan Sands
merge all zero-sized alloca's into one, fixing c43204g from the Ada ACATS conformance testsuite. What happened there was that a variable sized object was being allocated on the stack, "alloca i8, i32 %size". It was then being passed to another function, which tested that the address was not null (raising an exception if it was) then manipulated %size bytes in it (load and/or store). The optimizers cleverly managed to deduce that %size was zero (congratulations to them, as it isn't at all obvious), which made the alloca zero size, causing the optimizers to replace it with null, which then caused the check mentioned above to fail, and the exception to be raised, wrongly. Note that no loads and stores were actually being done to the alloca (the loop that does them is executed %size times, i.e. is not executed), only the not-null address check. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159202 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-25improve optimization of invoke instructions:Nuno Lopes
- simplifycfg: invoke undef/null -> unreachable - instcombine: invoke new -> invoke expect(0, 0) (an arbitrary NOOP intrinsic; only done if the allocated memory is unused, of course) - verifier: allow invoke of intrinsics (to make the previous step work) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159146 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-24llvm/lib: [CMake] Add explicit dependency to intrinsics_gen.NAKAMURA Takumi
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159112 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-22Revert remaining part of r93200: "Disable folding sext(trunc(x)) -> x"Jakob Stoklund Olesen
This fixes PR5997. These transforms were disabled because codegen couldn't deal with other uses of trunc(x). This is now handled by the peephole pass. This causes no regressions on x86-64. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159003 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21instcombine: disable optimization of 'invoke null/undef'. I'll move this ↵Nuno Lopes
functionality to SimplifyCFG (since we cannot make changes to the CFG here). Fixes the crashes with the attached test case git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158951 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21Look pass zext to strength reduce an udiv. Patch by David Majnemer. ↵Evan Cheng
rdar://11721329 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158946 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21Add support for invoke to the MemoryBuiltin analysid.Nuno Lopes
Update comments accordingly. Make instcombine remove useless invokes to C++'s 'new' allocation function (test attached). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158937 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21refactor the MemoryBuiltin analysis:Nuno Lopes
- provide more extensive set of functions to detect library allocation functions (e.g., malloc, calloc, strdup, etc) - provide an API to compute the size and offset of an object pointed by Move a few clients (GVN, AA, instcombine, ...) to the new API. This implementation is a lot more aggressive than each of the custom implementations being replaced. Patch reviewed by Nick Lewycky and Chandler Carruth, thanks. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158919 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20replace usage of EmitGEPOffset() with TargetData::getIndexedOffset() when ↵Nuno Lopes
the GEP offset is known to be constant. With this change, we avoid relying on the IR Builder to constant fold the operations. No functionality change intended. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158829 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-14InstCombine: fix a bug when combining (fcmp cc0 x, y) && (fcmp cc1 x, y).Manman Ren
uno && ueq was converted to ueq, it should be converted to uno. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158441 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-11InstCombine: factor code better.Benjamin Kramer
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158301 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-10InstCombine: Turn (zext A) == (B & (1<<X)-1) into A == (trunc B), narrowing ↵Benjamin Kramer
the compare. This saves a cast, and zext is more expensive on platforms with subreg support than trunc is. This occurs in the BSD implementation of memchr(3), see PR12750. On the synthetic benchmark from that bug stupid_memchr and bsd_memchr have the same performance now when not inlining either function. stupid_memchr: 323.0us bsd_memchr: 321.0us memchr: 479.0us where memchr is the llvm-gcc compiled bsd_memchr from osx lion's libc. When inlining is enabled bsd_memchr still regresses down to llvm-gcc memchr time, I haven't fully understood the issue yet, something is grossly mangling the loop after inlining. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158297 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-08canonicalize:Nuno Lopes
-%a + 42 into 42 - %a previously we were emitting: -(%a + 42) This fixes the infinite loop in PR12338. The generated code is still not perfect, though. Will work on that next git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158237 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-07Fix a bug in FoldSelectOpOp. Bitcast ops may change the number of vector ↵Nadav Rotem
elements, which may disagree with the select condition type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158166 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-06Fix combine of uno && ord -> false so that the ordering of the fcmps doesn'tChad Rosier
matter. rdar://11579835 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158084 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-28Fix suspicous hasOneUse() check, found by PVS Studio (PR12357).Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157592 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-28InstCombine: Fix infinite loop when encountering switch on trivial icmp.Benjamin Kramer
The test case feeds the following into InstCombine's visitSelect: %tobool8 = icmp ne i32 0, 0 %phitmp = select i1 %tobool8, i32 3, i32 0 Then instcombine replaces the right side of the switch with 0, doesn't notice that nothing changes and tries again indefinitely. This fixes PR12897. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157587 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-28switch AttrListPtr::get to take an ArrayRef, simplifying a lot of clients.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157556 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-27PR12967: Don't crash when trying to fold a shift that's larger than the ↵Benjamin Kramer
type's size. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157548 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-22add a new pass to instrument loads and stores for run-time bounds checkingNuno Lopes
move EmitGEPOffset from InstCombine to Transforms/Utils/Local.h (a draft of this) patch reviewed by Andrew, thanks. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157261 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-22revert my previous patches that introduced an additional parameter to the ↵Nuno Lopes
objectsize intrinsic. After a lot of discussion, we realized it's not the best option for run-time bounds checking git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157255 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-11objectsize: add a few more tests and fix a bugNuno Lopes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156625 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-11Fix a minor logic mistake transforming compares in instcombine. PR12514.Eli Friedman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156600 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-10objectsize: add support for GEPs with non-constant indexesNuno Lopes
add an additional parameter to InstCombiner::EmitGEPOffset() to force it to *not* emit operations with NUW flag git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156585 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-09objectsize:Nuno Lopes
refactor code a bit to enable future changes to support run-time information add support to compute allocation sizes at run-time if penalty > 1 (e.g., malloc(x), calloc(x, y), and VLAs) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156515 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-06Remove trailing spaces.Jakub Staszak
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156257 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-05Small fix in InstCombineCasts.cpp. Restored "alloca + bitcast" reducing for ↵Stepan Dyatkovskiy
case when alloca's size is calculated within the "add/sub/... nsw". Also added fix to 2011-06-13-nsw-alloca.ll test. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156231 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-03remove calls to calloc if the allocated memory is not used (it was already ↵Nuno Lopes
being done for malloc) fix a few typos found by Chad in my previous commit git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156110 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-03add support for calloc to objectsize loweringNuno Lopes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156102 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-03replace 'break's with 'return 0' in visitCallInst code for objectsize, since ↵Nuno Lopes
there is no need to fallback to visitCallSite. This gives a 0.9% in a test case git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156069 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-01Add support for llvm.arm.neon.vmull* intrinsics to InstCombine. FixesLang Hames
<rdar://problem/11291436>. This is a second attempt at a fix for this, the first was r155468. Thanks to Chandler, Bob and others for the feedback that helped me improve this. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155866 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-26Add instcombine patterns for the following transformations:Chad Rosier
(x & y) | (x ^ y) -> x | y (x & y) + (x ^ y) -> x | y Patch by Manman Ren. rdar://10770603 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155674 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-25Reverting r155468. Chris and Chandler have convinced me that it's dangerous andLang Hames
in poor taste. Talking through some alternate solutions with Chandler. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155530 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-24Add support for llvm.arm.neon.vmull* intrinsics to InstCombine. This fixesLang Hames
<rdar://problem/11291436>. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155468 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-23Reapply r155136 after fixing PR12599.Jakob Stoklund Olesen
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
2012-04-20Revert r155136 "Defer some shl transforms to DAGCombine."Jakob Stoklund Olesen
While the patch was perfect and defect free, it exposed a really nasty bug in X86 SelectionDAG that caused an llc crash when compiling lencod. I'll put the patch back in after fixing the SelectionDAG problem. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155181 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-19Defer some shl transforms to DAGCombine.Jakob Stoklund Olesen
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@155136 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-08Teach InstCombine to nuke a common alloca pattern -- an alloca which hasChandler Carruth
GEPs, bit casts, and stores reaching it but no other instructions. These often show up during the iterative processing of the inliner, SROA, and DCE. Once we hit this point, we can completely remove the alloca. These were actually showing up in the final, fully optimized code in a bunch of inliner tests I've been working on, and notably they show up after LLVM finishes optimizing away all function calls involved in hash_combine(a, b). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154285 91177308-0d34-0410-b5e6-96231b3b80d8
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