-cmmLintMachOpErr :: CmmExpr -> CmmLint a
-cmmLintMachOpErr expr = cmmLintErr (text "in MachOp application: " $$
- nest 2 (pprExpr expr))
+cmmLintMachOpErr :: CmmExpr -> [MachRep] -> [MachRep] -> CmmLint a
+cmmLintMachOpErr expr argsRep opExpectsRep
+ = cmmLintErr (text "in MachOp application: " $$
+ nest 2 (pprExpr expr) $$
+ (text "op is expecting: " <+> ppr opExpectsRep) $$
+ (text "arguments provide: " <+> ppr argsRep))