[llvm] [AggressiveCombine] Refactor `foldLoadsRecursive` to use `m_ShlOrSelf` (PR #155176)

[Nikita Popov via llvm-commits]

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@@ -646,11 +644,10 @@ static bool foldLoadsRecursive(Value *V, LoadOps &LOps, const DataLayout &DL,
 
   // Check if the pattern has loads
   LoadInst *LI1 = LOps.Root;
-  const APInt *ShAmt1 = LOps.Shift;
+  uint64_t ShAmt1 = LOps.Shift;
   if (LOps.FoundRoot == false &&
-      (match(X, m_OneUse(m_ZExt(m_Instruction(L1)))) ||
-       match(X, m_OneUse(m_Shl(m_OneUse(m_ZExt(m_OneUse(m_Instruction(L1)))),
-                               m_APInt(ShAmt1)))))) {
+      match(X, m_OneUse(
+                   m_ShlOrSelf(m_OneUse(m_ZExt(m_Instruction(L1))), ShAmt1)))) {
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nikic wrote:

As a followup, could check whether we can relax more of these one-use checks.

https://github.com/llvm/llvm-project/pull/155176