[mips][ias] Integers are not registers.

[dsanders]

Summary

When parseAnyRegister() encounters a symbol alias, it parses integers and adds
a corresponding expression to the operand list. This is clearly wrong since the
only operands that parseAnyRegister() should be accepting are registers.

It's not clear why this code was added and there are no test cases that cover
it. I think it might be leftover from when searchSymbolAlias() was more widely
used.

[sdardis]

LGTM.

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

if (Expr->getKind() == MCExpr::SymbolRef) {
             matchAnyRegisterNameWithoutDollar(Operands, DefSymbol.substr(1), S);
         if (ResTy == MatchOperand_Success) {
           Parser.Lex();
           return true;
         } else if (ResTy == MatchOperand_ParseFail)
           llvm_unreachable("Should never ParseFail");
         return false;
       }
-    } else if (Expr->getKind() == MCExpr::Constant) {
-      Parser.Lex();
-      const MCConstantExpr *Const = static_cast<const MCConstantExpr *>(Expr);
-      Operands.push_back(
-          MipsOperand::CreateImm(Const, S, Parser.getTok().getLoc(), *this));
-      return true;
     }
   }
   return false;
 }
 
 MipsAsmParser::OperandMatchResultTy
 MipsAsmParser::matchAnyRegisterNameWithoutDollar(OperandVector &Operands,
                                                  StringRef Identifier,

test/MC/Mips/cpsetup.s

 # N32-NEXT: R_MIPS_LO16/R_MIPS_NONE/R_MIPS_NONE __gnu_local_gp
 # N64-NEXT: R_MIPS_GPREL16/R_MIPS_SUB/R_MIPS_LO16  __cerror
 # N64-NEXT: daddu    $gp, $gp, $25
 
 # ASM-NEXT: .cpsetup $25, 8, __cerror
 
 # ALL-NEXT: nop
 
+t1b:
+IMM_8 = 8
+        .cpsetup $25, IMM_8, __cerror
+        nop
+        .cpreturn
+        nop
+
+# ALL-LABEL: t1b:
+# ASM-NEXT: IMM_8 = 8
+
+# O32-NOT: __cerror
+
+# NXX-NEXT: sd       $gp, 8($sp)
+# NXX-NEXT: lui      $gp, 0
+# N32-NEXT: R_MIPS_HI16/R_MIPS_NONE/R_MIPS_NONE __gnu_local_gp
+# N64-NEXT: R_MIPS_GPREL16/R_MIPS_SUB/R_MIPS_HI16  __cerror
+# NXX-NEXT: addiu    $gp, $gp, 0
+# N32-NEXT: R_MIPS_LO16/R_MIPS_NONE/R_MIPS_NONE __gnu_local_gp
+# N64-NEXT: R_MIPS_GPREL16/R_MIPS_SUB/R_MIPS_LO16  __cerror
+# N64-NEXT: daddu    $gp, $gp, $25
+
+# ASM-NEXT: .cpsetup $25, 8, __cerror
+
+# ALL-NEXT: nop
+
+# ASM-NEXT: .cpreturn
+# NXX-NEXT: ld $gp, 8($sp)
+
+# ALL-NEXT: nop
+