[llvm] [AArch64] merge index address with large offset into base address (PR #75343)

[David Green via llvm-commits]

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@@ -171,6 +178,13 @@ struct AArch64LoadStoreOpt : public MachineFunctionPass {
   findMatchingUpdateInsnForward(MachineBasicBlock::iterator I,
                                 int UnscaledOffset, unsigned Limit);
 
+  // Scan the instruction list to find a register assigned with a const
+  // value that can be combined with the current instruction (a load or store)
+  // using base addressing with writeback. Scan forwards.
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davemgreen wrote:

What does "Scan forwards." mean? It looks like it searches backward.

https://github.com/llvm/llvm-project/pull/75343