[llvm] [Sparc] Replace some CAS instructions with InstAlias (PR #65588)

[Sergei Barannikov via llvm-commits]

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@@ -464,6 +464,24 @@ def : InstAlias<"neg $rd", (SUBrr IntRegs:$rd, G0, IntRegs:$rd), 0>;
 // neg reg, rd -> sub %g0, reg, rd
 def : InstAlias<"neg $rs2, $rd", (SUBrr IntRegs:$rd, G0, IntRegs:$rs2), 0>;
 
+let Predicates = [HasV9] in {
+  // cas [rs1], rs2, rd -> casa [rs1] #ASI_P, rs2, rd
+  def : InstAlias<"cas [$rs1], $rs2, $rd",
+                  (CASArr IntRegs:$rd, IntRegs:$rs1, IntRegs:$rs2, 0x80), 0>;
+
+  // casl [rs1], rs2, rd -> casa [rs1] #ASI_P_L, rs2, rd
+  def : InstAlias<"casl [$rs1], $rs2, $rd",
+                  (CASArr IntRegs:$rd, IntRegs:$rs1, IntRegs:$rs2, 0x88), 0>;
+
+  // casx [rs1], rs2, rd -> casxa [rs1] #ASI_P, rs2, rd
+  def : InstAlias<"casx [$rs1], $rs2, $rd",
+                  (CASXArr I64Regs:$rd, I64Regs:$rs1, I64Regs:$rs2, 0x80), 0>;
+
+  // casxl [rs1], rs2, rd -> casxa [rs1] #ASI_P_L, rs2, rd
+  def : InstAlias<"casxl [$rs1], $rs2, $rd",
+                  (CASXArr I64Regs:$rd, I64Regs:$rs1, I64Regs:$rs2, 0x88), 0>;
+}
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s-barannikov wrote:

Changes to EmitPriority == 1 to reduce the number of changes in tests.


https://github.com/llvm/llvm-project/pull/65588