[llvm] [CFI][stackprobe] Shrink wrapper select safe prologue insertion block when inline stack probing is enabled (PR #81676)

[Momchil Velikov via llvm-commits]

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@@ -957,6 +957,15 @@ bool ShrinkWrap::runOnMachineFunction(MachineFunction &MF) {
   if (!ArePointsInteresting())
     return Changed;
 
+  const TargetLowering *TLI = MF.getSubtarget().getTargetLowering();
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momchil-velikov wrote:

Suggest placing this whole logic in `performShrinkWrapping` and/or `postShrinkWrapping`.
The test `TLI->isStackProbeInstrDefinedFlagRegLiveIn(Save)`  can quickly discard a block as a candidate for prologue/epilogue, so by placing it inside those functions we can avoid iterating over all instructions in a candidate block.

https://github.com/llvm/llvm-project/pull/81676