[llvm] [RISCV] Support zext.h mnemonic with Zbkb. (PR #96821)

[Pengcheng Wang via llvm-commits]

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@@ -28,7 +28,17 @@ roriw t0, t1, 0
 # CHECK-ASM: encoding: [0xbb,0x42,0x73,0x08]
 packw t0, t1, t2
 
-# Test the encoding used for zext.h
-# CHECK-ASM-AND-OBJ: packw t0, t1, zero
+# Test the encoding used for zext.h on RV64
+# CHECK-ASM: packw t0, t1, zero
+# CHECK-OBJ: zext.h t0, t1
 # CHECK-ASM: encoding: [0xbb,0x42,0x03,0x08]
 packw t0, t1, zero
+
+# Test the encoding used for zext.h on RV32
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wangpc-pp wrote:

This comment is not right.

https://github.com/llvm/llvm-project/pull/96821