[llvm] [Xtensa] Implement base CallConvention. (PR #83280)

[Matt Arsenault via llvm-commits]

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@@ -348,6 +367,67 @@ static SMLoc RefineErrorLoc(const SMLoc Loc, const OperandVector &Operands,
   return Loc;
 }
 
+bool XtensaAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
+                                         MCStreamer &Out,
+                                         const MCSubtargetInfo *STI) {
+  Inst.setLoc(IDLoc);
+  const unsigned Opcode = Inst.getOpcode();
+  switch (Opcode) {
+  case Xtensa::L32R: {
+    const MCSymbolRefExpr *OpExpr =
+        (const MCSymbolRefExpr *)Inst.getOperand(1).getExpr();
+    XtensaMCExpr::VariantKind Kind = XtensaMCExpr::VK_Xtensa_None;
+    const MCExpr *NewOpExpr = XtensaMCExpr::create(OpExpr, Kind, getContext());
+    Inst.getOperand(1).setExpr(NewOpExpr);
+  } break;
+  case Xtensa::MOVI: {
+    XtensaTargetStreamer &TS = this->getTargetStreamer();
+
+    // Expand MOVI operand
+    if (!Inst.getOperand(1).isExpr()) {
+      uint64_t ImmOp64 = Inst.getOperand(1).getImm();
+      int32_t Imm = ImmOp64;
+      if ((Imm < -2048) || (Imm > 2047)) {
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arsenm wrote:

!isInt<11>(Imm)?

https://github.com/llvm/llvm-project/pull/83280