[llvm] [RISCV] add more generic macrofusions (PR #151140)

[Craig Topper via llvm-commits]

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@@ -91,3 +91,94 @@ def TuneLDADDFusion
                    CheckIsImmOperand<2>,
                    CheckImmOperand<2, 0>
                  ]>>;
+
+// Fuse add with lw:
+//   add rd, rs1, rs2
+//   lw rd, 0(rd)
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topperc wrote:

Why only lw?

https://github.com/llvm/llvm-project/pull/151140