[llvm] [RISCV] Use TableGen-based macro fusion (PR #72224)

[Craig Topper via llvm-commits]

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@@ -0,0 +1,90 @@
+//==----- RISCVMacroFusion.td - Macro Fusion Definitions -----*- tablegen -*-=//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// ===---------------------------------------------------------------------===//
+// The following definitions describe the macro fusion predicators.
+
+// Fuse LUI followed by ADDI or ADDIW:
+//   rd = imm[31:0] which decomposes to
+//   lui rd, imm[31:12]
+//   addi(w) rd, rd, imm[11:0]
+def TuneLUIADDIFusion
+  : SimpleFusion<"lui-addi-fusion", "HasLUIADDIFusion",
+                 "Enable LUI+ADDI macro fusion",
+                 CheckOpcode<[LUI]>,
+                 CheckOpcode<[ADDI, ADDIW]>>;
+
+// Fuse AUIPC followed by ADDI:
+//   auipc rd, imm20
+//   addi rd, rd, imm12
+def TuneAUIPCADDIFusion
+  : SimpleFusion<"auipc-addi-fusion", "HasAUIPCADDIFusion",
+                 "Enable AUIPC+ADDI macrofusion",
+                 CheckOpcode<[AUIPC]>,
+                 CheckOpcode<[ADDI, ADDIW]>>;
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topperc wrote:

ADDIW should not be here

https://github.com/llvm/llvm-project/pull/72224