[AMDGPU] Add GFX12 encoding and aliases for existing SOP (SALU) instructions (#74305)

Author: jayfoad

llvm/lib/Target/AMDGPU/AMDGPU.td

@@ -1460,6 +1460,8 @@ def FeatureISAVersion12 : FeatureSet<
    FeatureExtendedImageInsts,
    FeaturePackedTID,
    FeatureVcmpxPermlaneHazard,
+   FeatureSALUFloatInsts,
+   FeatureVGPRSingleUseHintInsts,
    FeatureMADIntraFwdBug]>;
 
 //===----------------------------------------------------------------------===//

llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp

@@ -610,6 +610,10 @@ DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
                         Address, CS);
     if (Res) break;
 
+    Res = tryDecodeInst(DecoderTableGFX1232, MI, DW, Address, CS);
+    if (Res)
+      break;
+
     if (Bytes.size() < 4) break;
     const uint64_t QW = ((uint64_t)eatBytes<uint32_t>(Bytes) << 32) | DW;
 
@@ -637,6 +641,10 @@ DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
     Res = tryDecodeInst(DecoderTableGFX1064, MI, QW, Address, CS);
     if (Res) break;
 
+    Res = tryDecodeInst(DecoderTableGFX1264, MI, QW, Address, CS);
+    if (Res)
+      break;
+
     Res = tryDecodeInst(DecoderTableGFX1164, DecoderTableGFX11_FAKE1664, MI, QW,
                         Address, CS);
     if (Res)