[analyzer][NFC] Merge similar conditional paths

[steakhal]

I would probably query the opcode only once and reuse it, but is also fine.

Btw whats your intention making this change? Do you plan greater refactorings/cleanups?

[aaron.ballman]

LGTM (though I'd also be fine if we only wanted to call getOpcode() once).

[phyBrackets]

In D121045#3362373, @steakhal wrote:

I would probably query the opcode only once and reuse it, but is also fine.

Btw whats your intention making this change? Do you plan greater refactorings/cleanups?

Yeah, I think query the opcode once is a nice idea tho, let me do this in this patch only. And yeah I'm thinking of refactoring/cleanups where it needed and would love to make some big refactors. But I found this when I was looking into this issue (https://github.com/llvm/llvm-project/issues/53564 and needs to look at the deadstorechecker file.)

[phyBrackets]

query the opcode only once and reuse it

[phyBrackets]

Sorry but Idk why that DataFlowAnalysisIntro typo change also commited , I only add the deadstorechecker file.

[steakhal]

Shadowing potential names is not a good idea.
BTW OpCodes are often abbreviated to Op in variable names in this context.

clang/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp

110–112

[phyBrackets]

used the correct name for Opcode

[phyBrackets]

Thanks @steakhal !

clang/docs/DataFlowAnalysisIntro.md

 Putting it all together, to model the effects of a basic block we compute:
 
 ```
 out = transfer(basic_block, join(in_1, in_2, ..., in_n))
 ```
 
 (Note that there are other ways to write this equation that produce higher
 precision analysis results. The trick is to keep exploring the execution paths
-separately and delay joining until later. Hoowever, we won't discuss those
+separately and delay joining until later. However, we won't discuss those
 variations here.)
 
 To make a conclusion about all paths through the program, we repeat this
 computation on all basic blocks until we reach a fixpoint. In other words, we
 keep propagating information through the CFG until the computed sets of values
 stop changing.
 
 If the lattice has a finite height and transfer functions are monotonic the

clang/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp

 
 static const Expr *
 LookThroughTransitiveAssignmentsAndCommaOperators(const Expr *Ex) {
   while (Ex) {
     const BinaryOperator *BO =
       dyn_cast<BinaryOperator>(Ex->IgnoreParenCasts());
     if (!BO)
       break;
-    if (BO->getOpcode() == BO_Assign) {
-      Ex = BO->getRHS();
-      continue;
-    }
-    if (BO->getOpcode() == BO_Comma) {
+    BinaryOperatorKind Op = BO->getOpcode();
+    if (Op == BO_Assign || Op == BO_Comma) {
       Ex = BO->getRHS();
       continue;
     }
     break;
   }
   return Ex;
 }
 
 namespace {