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Minor cleanup - add accessors for a box's container result and address result.

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Swift SVN r15519
This commit is contained in:
Mark Lacey
2014-03-26 20:33:23 +00:00
parent 51672965f4
commit f02cdba27b
2 changed files with 15 additions and 9 deletions
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21
lib/SILPasses/AllocBoxToStack.cpp
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@@ -95,10 +95,12 @@ void getFinalReleases(AllocBoxInst *ABI,
auto seenRelease = false;
SILInstruction *OneRelease = nullptr;
auto Box = ABI->getContainerResult();
// We'll treat this like a liveness problem where the alloc_box is
// the def. Each block that has a use of the owning pointer has the
// value live-in unless it is the block with the alloc_box.
for (auto UI : SILValue(ABI, 0).getUses()) {
for (auto UI : Box.getUses()) {
auto *User = UI->getUser();
auto *BB = User->getParent();
@@ -132,7 +134,7 @@ void getFinalReleases(AllocBoxInst *ABI,
// release/dealloc.
for (auto *BB : UseBlocks)
if (!successorHasLiveIn(BB, LiveIn))
addLastRelease(SILValue(ABI, 0), BB, Releases);
addLastRelease(Box, BB, Releases);
}
/// optimizeAllocBox - Try to promote an alloc_box instruction to an
@@ -140,15 +142,15 @@ void getFinalReleases(AllocBoxInst *ABI,
/// remove the alloc_box itself.
static bool optimizeAllocBox(AllocBoxInst *ABI) {
// Scan all of the uses of the alloc_box to see if any of them cause the
// allocated memory to escape. If so, we can't promote it to the stack. If
// not, we can turn it into an alloc_stack.
if (canValueEscape(SILValue(ABI, 1)))
// Scan all of the uses of the alloc_box to see if any of them cause
// address of the held value to escape, in which case we can't
// promote it to live on the stack.
if (canValueEscape(ABI->getAddressResult()))
return false;
// Scan all of the uses of the retain count value, collecting all the releases
// and validating that we don't have an unexpected user.
for (auto UI : SILValue(ABI, 0).getUses()) {
for (auto UI : ABI->getContainerResult().getUses()) {
auto *User = UI->getUser();
if (isa<StrongRetainInst>(User))
@@ -178,8 +180,9 @@ static bool optimizeAllocBox(AllocBoxInst *ABI) {
auto *ASI = B1.createAllocStack(ABI->getLoc(), ABI->getElementType());
ASI->setDebugScope(ABI->getDebugScope());
// Replace all uses of the pointer operand with the spiffy new AllocStack.
SILValue(ABI, 1).replaceAllUsesWith(ASI->getAddressResult());
// Replace all uses of the address of the box's contained value with
// the address of the stack location.
ABI->getAddressResult().replaceAllUsesWith(ASI->getAddressResult());
// Check to see if the alloc_box was used by a mark_uninitialized instruction.
// If so, any uses of the pointer result need to keep using the MUI, not the