Loosen Globopt assert when called from HoistInvariantValueInfo #4567
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Fixes OS#15189393
Example:
confusedSym = ..[]; // non object value type
landingPad :
loopTop :
= LdElem[confusedSym + ...] // non-object value type in first pass, object value type in second pass
= LdFld[confusedSym...] // object value type
loopEnd
confusedSym is invariant in this loop, for some reason if we fail to hoist the LdFld, then this assert will fire when we try to hoist the LdElem.
Because optimization of LdFld will force combine the valuetype of confusedSym with Object, and in the second pass while optimizing LdElem in HoistInvariantValueInfo,
we will call ChangeValueInfo and this assert will fire.
This is because we are trying to change a non-object valuetype to an object valuetype.
AreValueTypesCompatible function converts to definite valuetypes before checking if they are compatible.
The check doesn't care if both of them are likely.
Globopt calls ChangeValueInfo with allowIncompatiblyTypes set to false in most cases where we are transforming specific to generic/generic to specific like Typespecialization etc.
It calls ChangeValueInfo with allowIncompatiblyTypes set to true, where we can expect incompatible types ex: UpdateObjPtrValueInfo.
This fix calls ChangeValueInfo from HoistInvariantValueInfo with allowIncompatiblyTypes set to true.
chakrabot
pushed a commit
that referenced
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Jan 18, 2018
…InvariantValueInfo Merge pull request #4567 from meg-gupta:lossenGlobOptAssert Fixes OS#15189393 Example: ``` invariantSym = ..[]; // non object value type landingPad : loopTop : = LdElem[invariantSym + ...] // non-object value type in first pass, object value type in second pass = LdFld[invariantSym...] // object value type loopEnd ``` invariantSym is invariant in this loop, for some reason if we fail to hoist the LdFld, then assert saying valueInfos are incompatible will fire, when we try to hoist the LdElem. Because optimization of LdFld will force combine the valuetype of invariantSym with Object, and in the second pass while optimizing LdElem in HoistInvariantValueInfo, we will call ChangeValueInfo and this assert will fire. This is because we are trying to change a non-object valuetype to an object valuetype. AreValueTypesCompatible function converts to definite valuetypes before checking if they are compatible. The check doesn't care if both of them are likely. Globopt calls ChangeValueInfo with allowIncompatiblyTypes set to false in most cases where we are transforming specific to generic/generic to specific like Typespecialization etc. It calls ChangeValueInfo with allowIncompatiblyTypes set to true, where we can expect incompatible types ex: UpdateObjPtrValueInfo. This fix calls ChangeValueInfo from HoistInvariantValueInfo with allowIncompatiblyTypes set to true.
chakrabot
pushed a commit
that referenced
this pull request
Jan 18, 2018
…from HoistInvariantValueInfo Merge pull request #4567 from meg-gupta:lossenGlobOptAssert Fixes OS#15189393 Example: ``` invariantSym = ..[]; // non object value type landingPad : loopTop : = LdElem[invariantSym + ...] // non-object value type in first pass, object value type in second pass = LdFld[invariantSym...] // object value type loopEnd ``` invariantSym is invariant in this loop, for some reason if we fail to hoist the LdFld, then assert saying valueInfos are incompatible will fire, when we try to hoist the LdElem. Because optimization of LdFld will force combine the valuetype of invariantSym with Object, and in the second pass while optimizing LdElem in HoistInvariantValueInfo, we will call ChangeValueInfo and this assert will fire. This is because we are trying to change a non-object valuetype to an object valuetype. AreValueTypesCompatible function converts to definite valuetypes before checking if they are compatible. The check doesn't care if both of them are likely. Globopt calls ChangeValueInfo with allowIncompatiblyTypes set to false in most cases where we are transforming specific to generic/generic to specific like Typespecialization etc. It calls ChangeValueInfo with allowIncompatiblyTypes set to true, where we can expect incompatible types ex: UpdateObjPtrValueInfo. This fix calls ChangeValueInfo from HoistInvariantValueInfo with allowIncompatiblyTypes set to true.
chakrabot
pushed a commit
that referenced
this pull request
Jan 18, 2018
… when called from HoistInvariantValueInfo Merge pull request #4567 from meg-gupta:lossenGlobOptAssert Fixes OS#15189393 Example: ``` invariantSym = ..[]; // non object value type landingPad : loopTop : = LdElem[invariantSym + ...] // non-object value type in first pass, object value type in second pass = LdFld[invariantSym...] // object value type loopEnd ``` invariantSym is invariant in this loop, for some reason if we fail to hoist the LdFld, then assert saying valueInfos are incompatible will fire, when we try to hoist the LdElem. Because optimization of LdFld will force combine the valuetype of invariantSym with Object, and in the second pass while optimizing LdElem in HoistInvariantValueInfo, we will call ChangeValueInfo and this assert will fire. This is because we are trying to change a non-object valuetype to an object valuetype. AreValueTypesCompatible function converts to definite valuetypes before checking if they are compatible. The check doesn't care if both of them are likely. Globopt calls ChangeValueInfo with allowIncompatiblyTypes set to false in most cases where we are transforming specific to generic/generic to specific like Typespecialization etc. It calls ChangeValueInfo with allowIncompatiblyTypes set to true, where we can expect incompatible types ex: UpdateObjPtrValueInfo. This fix calls ChangeValueInfo from HoistInvariantValueInfo with allowIncompatiblyTypes set to true.
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Fixes OS#15189393
Example:
invariantSym is invariant in this loop, for some reason if we fail to hoist the LdFld, then assert saying valueInfos are incompatible will fire, when we try to hoist the LdElem.
Because optimization of LdFld will force combine the valuetype of invariantSym with Object, and in the second pass while optimizing LdElem in HoistInvariantValueInfo,
we will call ChangeValueInfo and this assert will fire.
This is because we are trying to change a non-object valuetype to an object valuetype.
AreValueTypesCompatible function converts to definite valuetypes before checking if they are compatible.
The check doesn't care if both of them are likely.
Globopt calls ChangeValueInfo with allowIncompatiblyTypes set to false in most cases where we are transforming specific to generic/generic to specific like Typespecialization etc.
It calls ChangeValueInfo with allowIncompatiblyTypes set to true, where we can expect incompatible types ex: UpdateObjPtrValueInfo.
This fix calls ChangeValueInfo from HoistInvariantValueInfo with allowIncompatiblyTypes set to true.