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COWArrayOpt: Update for array addressor changes

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A mark_dependence use of the buffer is safe.

Swift SVN r24445
This commit is contained in:
Arnold Schwaighofer
2015-01-15 15:33:44 +00:00
parent 7f6824e74f
commit 0f4f6833c1
1 changed files with 24 additions and 0 deletions
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24
lib/SILPasses/COWArrayOpt.cpp
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@@ -531,6 +531,30 @@ bool COWArrayOpt::checkSafeArrayElementUse(SILInstruction *UseInst,
}
return true;
}
// Look for a safe mark_dependence instruction use.
// This use looks something like:
// %57 = load %56 : $*Builtin.BridgeObject from Array<Int>
// %58 = unchecked_ref_bit_cast %57 : $Builtin.BridgeObject to $_ContiguousArr
// %59 = unchecked_ref_cast %58 : $_ContiguousArrayStorageBase to $Builtin.Nat
// %60 = struct_extract %53 : $UnsafeMutablePointer<Int>, #UnsafeMutablePointe
// %61 = pointer_to_address %60 : $Builtin.RawPointer to $*Int
// %62 = mark_dependence %61 : $*Int on %59 : $Builtin.NativeObject
if (isa<MarkDependenceInst>(UseInst))
return true;
if (auto *UCRBC = dyn_cast<UncheckedRefBitCastInst>(UseInst)) {
for (auto U : UCRBC->getUses())
if (!checkSafeArrayElementUse(U->getUser(), ArrayVal))
return false;
return true;
}
if (auto *UCRC = dyn_cast<UncheckedRefCastInst>(UseInst)) {
for (auto U : UCRC->getUses())
if (!checkSafeArrayElementUse(U->getUser(), ArrayVal))
return false;
return true;
}
// Found an unsafe or unknown user. The Array may escape here.
DEBUG(llvm::dbgs() << " Skipping Array: unknown Element use!\n"
<< *UseInst);