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path: root/lib/Analysis/BasicAliasAnalysis.cpp
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2008-06-16simplify some code by using a helper function. This really reallyChris Lattner
wants a 'nocapture' predicate. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52304 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16move a bunch of predicates up into their own sectionChris Lattner
in this file, no other changes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52303 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16Other parts of this code treat noalias arguments as objects forChris Lattner
the purposes of escape analysis. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52302 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16If we are checking to see if the result of a call aliases aChris Lattner
pointer derived from a local allocation, if the local allocation never escapes, the pointers can't alias. This implements PR2436 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52301 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16Refactor basicaa's main alias function somethin' fierce. Chris Lattner
This fixes several minor bugs (such as returning noalias for comparisons between external weak functions an null) but is mostly a cleanup. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52299 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-02Fixes PR2395. Looking for a constant in a GEP tail (when the first GEP Wojciech Matyjewicz
is longer than the second one) should stop after finding one. Added break instruction guarantees it. It also changes difference between offsets to absolute value of this difference in the condition. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51875 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-13Clean up the use of static and anonymous namespaces. This turned upDan Gohman
several things that were neither in an anonymous namespace nor static but not intended to be global. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51017 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21Fix a "large integer implicitly truncated to unsigned type"Duncan Sands
warning. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50033 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-15Don't assume a tail call can't reference a byvalDale Johannesen
argument to the outer function, this isn't correct. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49731 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-20Restore isCFGOnly property of various analysis passes.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48579 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-19PassInfo keep tracks whether a pass is an analysis pass or not.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48554 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19Fix a compiler warning.Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47328 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19In addition to arguments passed to it, memcpy (and all other calls) can ↵Owen Anderson
ModRef pointers that alias their arguments as well. This fixes PR2057. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47317 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18don't bother calling getUnderlyingObject for non-pointers.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47272 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18Since we're not checking for the more general AllocationInst first, we need ↵Owen Anderson
to explicitly check that Object is an Argument before casting it to one. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47268 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18This check is not correct for mallocs, so exclude them earlier.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47263 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18Fix a comment, and a bug where we weren't applying the tail call logic in ↵Owen Anderson
cases that failed the first test. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47253 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18Fix bugs that Chris noticed in my last patch.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47252 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18bitcasts of pointers are always pointers.Chris Lattner
If we see a memcpy of a pointer, make sure to check later uses of the pointer as well. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47250 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-17Teach getModRefInfo that memcpy, memmove, and memset don't "capture" memory ↵Owen Anderson
addresses. Also, noalias arguments are be considered "like" stack allocated ones for this purpose, because the only way they can be modref'ed is if they escape somewhere in the current function. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47247 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-24getUnderlyingObject can return null, handle this.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46318 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-24Teach basicaa that 'byval' arguments define a new memory location thatChris Lattner
can't be aliased to other known objects. This allows us to know that byval pointer args don't alias globals, etc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46315 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29Remove attribution from file headers, per discussion on llvmdev.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45418 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-13Make these loops follow GetGEPOperands() behavior.Wojciech Matyjewicz
Let: %q = GEP %p, X, ... If %p is a GEP, we can chase baseptr further, only if X==0. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44999 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-09Fix PR1782, patch by Wojtek Matyjewicz!Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44733 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-03Rather than having special rules like "intrinsics cannotDuncan Sands
throw exceptions", just mark intrinsics with the nounwind attribute. Likewise, mark intrinsics as readnone/readonly and get rid of special aliasing logic (which didn't use anything more than this anyway). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44544 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-01Integrate the readonly/readnone logic more deeplyDuncan Sands
into alias analysis. This meant updating the API which now has versions of the getModRefBehavior, doesNotAccessMemory and onlyReadsMemory methods which take a callsite parameter. These should be used unless the callsite is not known, since in general they can do a better job than the versions that take a function. Also, users should no longer call the version of getModRefBehavior that takes both a function and a callsite. To reduce the chance of misuse it is now protected. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44487 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-28Add some convenience methods for querying attributes, andDuncan Sands
use them. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44403 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-27Fix PR1146: parameter attributes are longer part ofDuncan Sands
the function type, instead they belong to functions and function calls. This is an updated and slightly corrected version of Reid Spencer's original patch. The only known problem is that auto-upgrading of bitcode files doesn't seem to work properly (see test/Bitcode/AutoUpgradeIntrinsics.ll). Hopefully a bitcode guru (who might that be? :) ) will fix it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44359 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-23Ding dong, the DoesntAccessMemoryFns andDuncan Sands
OnlyReadsMemoryFns tables are dead! We get more, and more accurate, information from gcc via the readnone and readonly function attributes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44288 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-22Teach alias analysis about readnone/readonly functions.Duncan Sands
Based on a patch by Török Edwin. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44279 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-16Fix for PR1801Tanya Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44193 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-06Fix PR1774 and BasicAA/2007-11-05-SizeCrash.llChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43756 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-01Executive summary: getTypeSize -> getTypeStoreSize / getABITypeSize.Duncan Sands
The meaning of getTypeSize was not clear - clarifying it is important now that we have x86 long double and arbitrary precision integers. The issue with long double is that it requires 80 bits, and this is not a multiple of its alignment. This gives a primitive type for which getTypeSize differed from getABITypeSize. For arbitrary precision integers it is even worse: there is the minimum number of bits needed to hold the type (eg: 36 for an i36), the maximum number of bits that will be overwriten when storing the type (40 bits for i36) and the ABI size (i.e. the storage size rounded up to a multiple of the alignment; 64 bits for i36). This patch removes getTypeSize (not really - it is still there but deprecated to allow for a gradual transition). Instead there is: (1) getTypeSizeInBits - a number of bits that suffices to hold all values of the type. For a primitive type, this is the minimum number of bits. For an i36 this is 36 bits. For x86 long double it is 80. This corresponds to gcc's TYPE_PRECISION. (2) getTypeStoreSizeInBits - the maximum number of bits that is written when storing the type (or read when reading it). For an i36 this is 40 bits, for an x86 long double it is 80 bits. This is the size alias analysis is interested in (getTypeStoreSize returns the number of bytes). There doesn't seem to be anything corresponding to this in gcc. (3) getABITypeSizeInBits - this is getTypeStoreSizeInBits rounded up to a multiple of the alignment. For an i36 this is 64, for an x86 long double this is 96 or 128 depending on the OS. This is the spacing between consecutive elements when you form an array out of this type (getABITypeSize returns the number of bytes). This is TYPE_SIZE in gcc. Since successive elements in a SequentialType (arrays, pointers and vectors) need to be aligned, the spacing between them will be given by getABITypeSize. This means that the size of an array is the length times the getABITypeSize. It also means that GEP computations need to use getABITypeSize when computing offsets. Furthermore, if an alloca allocates several elements at once then these too need to be aligned, so the size of the alloca has to be the number of elements multiplied by getABITypeSize. Logically speaking this doesn't have to be the case when allocating just one element, but it is simpler to also use getABITypeSize in this case. So alloca's and mallocs should use getABITypeSize. Finally, since gcc's only notion of size is that given by getABITypeSize, if you want to output assembler etc the same as gcc then getABITypeSize is the size you want. Since a store will overwrite no more than getTypeStoreSize bytes, and a read will read no more than that many bytes, this is the notion of size appropriate for alias analysis calculations. In this patch I have corrected all type size uses except some of those in ScalarReplAggregates, lib/Codegen, lib/Target (the hard cases). I will get around to auditing these too at some point, but I could do with some help. Finally, I made one change which I think wise but others might consider pointless and suboptimal: in an unpacked struct the amount of space allocated for a field is now given by the ABI size rather than getTypeStoreSize. I did this because every other place that reserves memory for a type (eg: alloca) now uses getABITypeSize, and I didn't want to make an exception for unpacked structs, i.e. I did it to make things more uniform. This only effects structs containing long doubles and arbitrary precision integers. If someone wants to pack these types more tightly they can always use a packed struct. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43620 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-26Make a comment better.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43379 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-25Fix for PR1741.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43326 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-07Add lengthof and endof templates that hide a lot of sizeof computations.Owen Anderson
Patch by Sterling Stein! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41758 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-05Missing break. Patch by Wojciech Matyjewicz.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41727 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-06This resolves a regression of BasicAA which failed to find any memory ↵Chandler Carruth
information for overloaded intrinsics (PR1600). This resolves that issue, and improves the matching scheme to use a BitVector rather than a binary search. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40872 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-05Upgrade BasicAliasAnalysis::getModRefBehavior to not call Value::getName,Chris Lattner
which dynamically allocates the string result. This speeds up dse on the testcase from PR1432 from 0.3781s to 0.1804s (2.1x). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40838 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-02Implement review feedback.Christopher Lamb
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40745 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-02Teach BasicAA about noalias parameter attributes, but do it correctly this time.Christopher Lamb
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40711 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-31Revert overly aggressive interpretation of noaliasChristopher Lamb
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40635 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-31Teach BasicAA about noalias function parameters. Passes all of DejaGNU and ↵Christopher Lamb
test-suite. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40624 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-16Fix comments about vectors to use the current wording.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39921 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-02Add explicit keywords.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37839 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-18Make BasicAliasAnalysis correctly register itself. Patch by DevangAnton Korobeynikov
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37627 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-03Drop 'const'Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36662 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-02Use 'static const char' instead of 'static const int'.Devang Patel
Due to darwin gcc bug, one version of darwin linker coalesces static const int, which defauts PassID based pass identification. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36652 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-01Do not use typeinfo to identify pass in pass manager.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36632 91177308-0d34-0410-b5e6-96231b3b80d8