[llvm] [AMDGPU] Merge consecutive wait_alu instruction (PR #128916)

[Nicolai Hähnle via llvm-commits]

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@@ -1780,6 +1800,22 @@ unsigned encodeFieldVaVcc(unsigned VaVcc) {
   return encodeFieldVaVcc(0xffff, VaVcc);
 }
 
+unsigned encodeFieldVaSsrc(unsigned Encoded, unsigned VaSsrc) {
+  return packBits(VaSsrc, Encoded, getVaSsrcBitShift(), getVaSsrcBitWidth());
+}
+
+unsigned encodeFieldVaSsrc(unsigned VaSsrc) {
+  return encodeFieldVaSsrc(0xfff, VaSsrc);
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nhaehnle wrote:

Should be 0xffff?

https://github.com/llvm/llvm-project/pull/128916