[llvm] [Xtensa] Implement Code Density Option. (PR #119639)

[Andrei Safronov via llvm-commits]

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@@ -0,0 +1,63 @@
+# RUN: llvm-mc %s -triple=xtensa -show-encoding --mattr=+density \
+# RUN:     | FileCheck -check-prefixes=CHECK,CHECK-INST %s
+
+.align	4
+LBL0:
+
+# Instruction format RRRN
+# CHECK-INST: add.n a2, a3, a4
+# CHECK: encoding: [0x4a,0x23]
+add.n a2, a3, a4
+
+# Instruction format RRRN
+# CHECK-INST: addi.n a2, a3, 3
+# CHECK: encoding: [0x3b,0x23]
+addi.n a2, a3, 3
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andreisfr wrote:

I added test case.

https://github.com/llvm/llvm-project/pull/119639