Fix unreachable-break issue in cinderx/Jit/lir/generator.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: D78276025

fbshipit-source-id: bf2543b9c6e61b7a934e8eaf6510d8a3092c5161

Author: r-barnes

Jit/lir/generator.cpp

@@ -821,7 +821,6 @@ LIRGenerator::TranslatedBlock LIRGenerator::TranslateOneBasicBlock(
             break;
           default:
             JIT_ABORT("not implemented");
-            break;
         }
 
         if (helper != 0) {
@@ -883,7 +882,6 @@ LIRGenerator::TranslatedBlock LIRGenerator::TranslateOneBasicBlock(
           }
           default: {
             JIT_ABORT("Invalid operation for DoubleBinaryOp");
-            break;
           }
         }
 
@@ -926,7 +924,6 @@ LIRGenerator::TranslatedBlock LIRGenerator::TranslateOneBasicBlock(
             break;
           default:
             JIT_ABORT("Not implemented {}", static_cast<int>(instr->op()));
-            break;
         }
         bbb.appendInstr(instr->output(), op, instr->left(), instr->right());
         break;
@@ -1120,7 +1117,6 @@ LIRGenerator::TranslatedBlock LIRGenerator::TranslateOneBasicBlock(
           default:
             JIT_ABORT(
                 "Not implemented unary op {}", static_cast<int>(instr->op()));
-            break;
         }
         break;
       }
@@ -1169,7 +1165,6 @@ LIRGenerator::TranslatedBlock LIRGenerator::TranslateOneBasicBlock(
       }
       case Opcode::kAssign: {
         JIT_CHECK(false, "assign shouldn't be present");
-        break;
       }
       case Opcode::kBitCast: {
         // BitCasts are purely informative

Jit/lir/postalloc.cpp

@@ -371,7 +371,6 @@ RewriteResult rewriteBitExtensionInstrs(instr_iter_t instr_iter) {
     case OperandBase::k64bit:
     case OperandBase::kObject:
       JIT_ABORT("can't be smaller than the maximum size");
-      break;
     case OperandBase::kDouble:
       JIT_ABORT("A float point number cannot be the input of the instruction.");
   }