search for: getclobber

...odRef: // If the call has no effect on the queried pointer, just ignore it. continue; case AliasAnalysis::Mod: // If we're in an invariant region, we can ignore calls that ONLY // modify the pointer. if (InvariantTag) continue; return MemDepResult::getClobber(Inst); case AliasAnalysis::Ref: // If the call is known to never store to the pointer, and if this is a // load query, we can safely ignore it (scan past it). if (isLoad) continue; +++ return MemDepResult::getDef(Inst); default: // Otherwise, there...

...hy should a read-only call (which yields AliasAnalysis::Ref and is handled in this code fragment) be any different from e.g. a load. Isn't a read-only call effectively just a series of loads from a memory-dependence perspective? In other words, why does this code fragment return MemDepResult::getClobber() instead of MemDepResult::getDef() for a read-only call? On Sat, Jul 17, 2010 at 6:18 PM, Eugene Toder <eltoder at gmail.com> wrote: > Since isLoad == false means we're looking at a store, what this does > is making the store *p depend on the load *p. This is correct -- you >...

...as no effect on the queried pointer, just ignore it. >        continue; >      case AliasAnalysis::Mod: >        // If we're in an invariant region, we can ignore calls that ONLY >        // modify the pointer. >        if (InvariantTag) continue; >        return MemDepResult::getClobber(Inst); >      case AliasAnalysis::Ref: >        // If the call is known to never store to the pointer, and if this is > a >        // load query, we can safely ignore it (scan past it). >        if (isLoad) >          continue; > +++    return MemDepResult::getDef(Inst); >  ...

...ll (which yields > AliasAnalysis::Ref and is handled in this code fragment) be any different > from e.g. a load.  Isn't a read-only call effectively just a series of loads > from a memory-dependence perspective? > In other words, why does this code fragment return > MemDepResult::getClobber() instead of MemDepResult::getDef() for a read-only > call? > On Sat, Jul 17, 2010 at 6:18 PM, Eugene Toder <eltoder at gmail.com> wrote: >> >> Since isLoad == false means we're looking at a store, what this does >> is making the store *p depend on the load *p. Thi...

...if (MR == AliasAnalysis::ModRef) MR = AA->callCapturesBefore(Inst, MemLoc, DT); switch (MR) { case AliasAnalysis::NoModRef: // If the call has no effect on the queried pointer, just ignore it. continue; case AliasAnalysis::Mod: return MemDepResult::getClobber(Inst); case AliasAnalysis::Ref: // If the call is known to never store to the pointer, and if this is a // load query, we can safely ignore it (scan past it). if (isLoad) continue; default: // Otherwise, there is a potential dependence. Return a clob...

...9;t know about any > // phi translation that may have happened along the way. > > // If we have a partial alias, then return this as a clobber for > the > // client to handle. > if (R == AliasAnalysis::PartialAlias) > return MemDepResult::getClobber(Inst); > #endif > > > > > > > Conservative new patch attached. > > > > > > > > (Note that i still updated the testcases, because we will *never* be > > able to legally return PartialAlias as they were written) > > > > Yes, sounds goo...

...ly, it doesn't know about any > > // phi translation that may have happened along the way. > > > > // If we have a partial alias, then return this as a clobber for the > > // client to handle. > > if (R == AliasAnalysis::PartialAlias) > > return MemDepResult::getClobber(Inst) ; > > #endif > > > > > > > > > > > Conservative new patch attached. > > > > > > > > > > > > (Note that i still updated the testcases, because we will *never* > > > be > > > able to legally return Part...

This patch adds EmitTypeAuxAttribute() function to CGDebugInfo, which allows other parts of clang issue auxiliary information through an enumeration type in Dwarf information. For example, by calling DI->EmitTypeAuxAttribute(type, "ID", 1234); We can get following information in dwarf: <1><3f>: Abbrev Number: 3 (DW_TAG_structure_type) <40> DW_AT_name

...t know about any > > // phi translation that may have happened along the way. > > > > // If we have a partial alias, then return this as a clobber for > > the > > // client to handle. > > if (R == AliasAnalysis::PartialAlias) > > return MemDepResult::getClobber(Inst) ; > > #endif > > > > > > > > > > > Conservative new patch attached. > > > > > > > > > > > > (Note that i still updated the testcases, because we will *never* > > > be > > > able to legally...

So, I can make all these testcases work, but it's a little tricky (it involves tracking some things, like GEP byte range, and then checking bases and using getObjectSize, much like BasicAA does). Because i really don't want to put that much "not well tested" code in a bugfix, and honestly, i'm not sure we will catch any cases here that BasicAA does not, i've attached a

...hat may have happened along the way. >>> > >>> > // If we have a partial alias, then return this as a clobber for >>> > the >>> > // client to handle. >>> > if (R == AliasAnalysis::PartialAlias) >>> > return MemDepResult::getClobber(Inst) ; >>> > #endif >>> > >>> > > >>> > > >>> > > Conservative new patch attached. >>> > > >>> > > >>> > > >>> > > (Note that i still updated the testcases, bec...

...t know about any > > // phi translation that may have happened along the way. > > > > // If we have a partial alias, then return this as a clobber for > > the > > // client to handle. > > if (R == AliasAnalysis::PartialAlias) > > return MemDepResult::getClobber(Inst) ; > > #endif > > > > > > > > > > > Conservative new patch attached. > > > > > > > > > > > > (Note that i still updated the testcases, because we will *never* > > > be > > > able to legally...

...gt; // phi translation that may have happened along the way. > > > > > > // If we have a partial alias, then return this as a clobber for > > > the > > > // client to handle. > > > if (R == AliasAnalysis::PartialAlias) > > > return MemDepResult::getClobber(Inst) ; > > > #endif > > > > > > > > > > > > > > > Conservative new patch attached. > > > > > > > > > > > > > > > > (Note that i still updated the testcases, because we will *never* > > >...

...y have happened along the way. > > > > > > > > // If we have a partial alias, then return this as a clobber for > > > > the > > > > // client to handle. > > > > if (R == AliasAnalysis::PartialAlias) > > > > return MemDepResult::getClobber(Inst) ; > > > > #endif > > > > > > > > > > > > > > > > > > > Conservative new patch attached. > > > > > > > > > > > > > > > > > > > > (Note that i still updated the testc...