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llvm-svn: 36213
This commit is contained in:
Anton Korobeynikov 2007-04-17 19:34:00 +00:00
parent 9ad682ad80
commit 60de2ce283

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@ -3406,8 +3406,17 @@ SDOperand X86TargetLowering::LowerCALL(SDOperand Op, SelectionDAG &DAG) {
}
}
// Lower dynamic stack allocation to _alloca call for Cygwin/Mingw targets.
// Calls to _alloca is needed to probe the stack when allocating more than 4k
// bytes in one go. Touching the stack at 4K increments is necessary to ensure
// that the guard pages used by the OS virtual memory manager are allocated in
// correct sequence.
SDOperand X86TargetLowering::LowerDYNAMIC_STACKALLOC(SDOperand Op,
SelectionDAG &DAG) {
assert(Subtarget->isTargetCygMing() &&
"This should be used only on Cygwin/Mingw targets");
// Get the inputs.
SDOperand Chain = Op.getOperand(0);
SDOperand Size = Op.getOperand(1);