Eastimate required stack alignment early, so we can decide, whether we will need frame pointer or not
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50161 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index 46bf76f..2baf360 100644
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -372,6 +372,25 @@
}
void
+X86RegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
+ RegScavenger *RS) const {
+ MachineFrameInfo *FFI = MF.getFrameInfo();
+
+ // Calculate and set max stack object alignment early, so we can decide
+ // whether we will need stack realignment (and thus FP).
+ unsigned MaxAlign = 0;
+ for (int i = FFI->getObjectIndexBegin(),
+ e = FFI->getObjectIndexEnd(); i != e; ++i) {
+ if (FFI->isDeadObjectIndex(i))
+ continue;
+ unsigned Align = FFI->getObjectAlignment(i);
+ MaxAlign = std::max(MaxAlign, Align);
+ }
+
+ FFI->setMaxAlignment(MaxAlign);
+}
+
+void
X86RegisterInfo::processFunctionBeforeFrameFinalized(MachineFunction &MF) const{
X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
int32_t TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta();