[llvm] [VPlan] Add vputils::reconstructSSA (PR #212209)

[Luke Lau via llvm-commits]

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@@ -221,6 +221,13 @@ SmallVector<VPUser *> collectUsersRecursively(VPValue *V);
 VPIRValue *tryToFoldLiveIns(VPSingleDefRecipe &R, ArrayRef<VPValue *> Operands,
                             const DataLayout &DL);
 
+/// Insert phis to reconstruct SSA for a single value starting from \p VPBB. \p
+/// Defs is a map of definitions at specific blocks. Returns the
+/// reconstructed value at VPBB. Use if the CFG has been modified such that a
+/// def no longer dominates all its uses. VPBB must be reachable from the entry.
+LLVM_ABI_FOR_TEST VPValue *
+reconstructSSA(VPBasicBlock *VPBB, DenseMap<VPBasicBlock *, VPValue *> Defs);
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lukel97 wrote:

Yeah good point, updated in cf604e841b5f88ea963abb03d3c2d7d719969a01

https://github.com/llvm/llvm-project/pull/212209