[llvm] [VPlan] Insert VPBlendRecipes in post order. NFC (PR #201782)

[Luke Lau via llvm-commits]

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@@ -136,6 +138,12 @@ void VPPredicator::createBlockInMask(VPBasicBlock *VPBB) {
   // Start inserting after the block's phis, which be replaced by blends later.
   Builder.setInsertPoint(VPBB, VPBB->getFirstNonPhi());
 
+  // Keep track of where in VPBB we are inserting the masks into.
+  scope_exit UpdateInsertPoint([this, &VPBB]() {
+    assert(!InsertPoints.contains(VPBB) && "InsertPoint clobbered?");
+    InsertPoints[VPBB] = Builder.getInsertPoint();
+  });
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lukel97 wrote:

We don't reset the insert point but it changes when new edge masks or block in-masks are created. Although I think we can just recalculate the insert point based off of the block-in mask. I've removed the InsertPoints map in 73427ee2b2dec03dd65f9f6c65e4bb0d31a969f6

https://github.com/llvm/llvm-project/pull/201782