Fix unreachable-break issue in cinderx/Jit/hir/builder.cpp +5

Summary:
LLVM has a warning `-Wunreachable-code-break` which identifies `break` statements that cannot be reached. These compromise readability, are misleading, and may identify bugs. This diff removes such statements.

Such statements once existed to prevent accidental fallthroughs in switch statements. However, this is no longer necessary in C++17 because `[[fallthrough]]` is used to indicate intentional fallthroughs and we raise compilation errors for fallthroughs that are not annotated with `[[fallthrough]]` using `-Wimplicit-fallthrough`.

For questions/comments, contact r-barnes.

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Reviewed By: dtolnay

Differential Revision: D78275962

fbshipit-source-id: 58dde2d33830cc9eb0eab94a675811b186c763fc

Author: r-barnes

Jit/hir/builder.cpp

@@ -478,7 +478,6 @@ static bool should_snapshot(
     case WITH_EXCEPT_START: {
       JIT_ABORT(
           "Should not be compiling except blocks (opcode {})\n", bci.opcode());
-      break;
     }
     // Take a snapshot after translating all other bytecode instructions. This
     // may generate unnecessary deoptimization metadata but will always be
@@ -1197,7 +1196,6 @@ void HIRBuilder::translate(
           // BytecodeInstruction::getJumpTarget() to always skip the END_FOR so
           // that block should never be processed.
           JIT_ABORT("We should never cross an END_FOR in the HIR builder");
-          break;
         }
         case SETUP_FINALLY: {
           emitSetupFinally(tc, bc_instr);
@@ -1482,7 +1480,6 @@ void HIRBuilder::translate(
               bc_instr.opcode());
         default: {
           JIT_ABORT("Unhandled opcode: {}", bc_instr.opcode());
-          break;
         }
       }
     }
@@ -2098,7 +2095,6 @@ static inline UnaryOpKind get_unary_op_kind(
     default:
       JIT_ABORT("Unhandled unary op {}", bc_instr.opcode());
       // NOTREACHED
-      break;
   }
 }
 
@@ -2651,7 +2647,6 @@ void HIRBuilder::emitJumpIf(
       // NOTREACHED
       JIT_ABORT(
           "Trying to translate non-jump-if bytecode: {}", bc_instr.opcode());
-      break;
     }
   }
 
@@ -3096,7 +3091,6 @@ static inline BinaryOpKind get_primitive_bin_op_kind(
     default: {
       JIT_ABORT("Unhandled binary op {}", bc_instr.oparg());
       // NOTREACHED
-      break;
     }
   }
 }
@@ -3130,7 +3124,6 @@ static inline bool is_double_binop(int oparg) {
     default: {
       JIT_ABORT("Invalid binary op {}", oparg);
       // NOTREACHED
-      break;
     }
   }
 }
@@ -3147,7 +3140,6 @@ static inline Type element_type_from_seq_type(int seq_type) {
     default:
       JIT_ABORT("Invalid sequence type: ({})", seq_type);
       // NOTREACHED
-      break;
   }
 }
 
@@ -3217,7 +3209,6 @@ void HIRBuilder::emitPrimitiveCompare(
       break;
     default:
       JIT_ABORT("unsupported comparison");
-      break;
   }
   tc.emit<PrimitiveCompare>(result, op, left, right);
   stack.push(result);
@@ -3255,7 +3246,6 @@ void HIRBuilder::emitPrimitiveUnaryOp(
     }
     default: {
       JIT_ABORT("unsupported unary op");
-      break;
     }
   }
   tc.frame.stack.push(result);
@@ -3655,7 +3645,6 @@ void HIRBuilder::emitPopJumpIf(
       // NOTREACHED
       JIT_ABORT(
           "Trying to translate non pop-jump bytecode: {}", bc_instr.opcode());
-      break;
     }
   }
 
@@ -4215,7 +4204,6 @@ void HIRBuilder::emitRaiseVarargs(
       break;
     default:
       JIT_ABORT("Unsupported RAISE_VARARGS op: {}", bc_instr.oparg());
-      break;
   }
 }
 

Jit/hir/hir.cpp

@@ -609,7 +609,6 @@ static void postorder_traverse(
       /* NOTREACHED */
       JIT_ABORT(
           "Block {} has invalid terminator {}", block->id, instr->opname());
-      break;
     }
   }
 

Jit/hir/optimization.cpp

@@ -661,7 +661,6 @@ static void simplifyRedundantCondBranches(CFG* cfg) {
       default:
         // Can't be sure that it's safe to replace the instruction with a branch
         JIT_ABORT("Unknown side effects of {} instruction", term->opname());
-        break;
     }
     to_simplify.emplace_back(&block);
   }

Jit/hir/parser.cpp

@@ -1039,7 +1039,6 @@ HIRParser::parseInstr(std::string_view opcode, Register* dst, int bb_index) {
     case Opcode::kYieldFrom:
     case Opcode::kYieldFromHandleStopAsyncIteration: {
       JIT_ABORT("Unsupported opcode: {}", opcode);
-      break;
     }
   }
 
@@ -1302,7 +1301,6 @@ RegState HIRParser::GetNextRegState() {
       break;
     default:
       JIT_ABORT("Unknown ref kind: {}", token[0]);
-      break;
   }
 
   return rs;

Jit/hir/preload.cpp

@@ -53,7 +53,6 @@ Type prim_type_to_type(int prim_type) {
       return TCInt32;
     default:
       JIT_ABORT("Non-primitive or unsupported Python type: {}", prim_type);
-      break;
   }
 }