[clang][NFC] Move Diags.isIgnored check later in checkForRedundantLoop

[tbaederr]

... Iteration.

The isIgnored() check is more expensive than the earlier checks, so move it last.

[llvmbot]

@llvm/pr-subscribers-clang

Author: Timm Baeder (tbaederr)

Changes

... Iteration.

---

Full diff: https://github.com/llvm/llvm-project/pull/141470.diff

1 Files Affected:

• (modified) clang/lib/Sema/SemaStmt.cpp (+4-4)

diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index ed070649dc1f9..6d6da6e7fdd8c 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -2207,16 +2207,16 @@ namespace {
     // Return when there is nothing to check.
     if (!Body || !Third) return;
 
-    if (S.Diags.isIgnored(diag::warn_redundant_loop_iteration,
-                          Third->getBeginLoc()))
-      return;
-
     // Get the last statement from the loop body.
     CompoundStmt *CS = dyn_cast<CompoundStmt>(Body);
     if (!CS || CS->body_empty()) return;
     Stmt *LastStmt = CS->body_back();
     if (!LastStmt) return;
 
+    if (S.Diags.isIgnored(diag::warn_redundant_loop_iteration,
+                          Third->getBeginLoc()))
+      return;
+
     bool LoopIncrement, LastIncrement;
     DeclRefExpr *LoopDRE, *LastDRE;
 

[shafik]

Can you elaborate in your summary.

I am guessing because the other checks are a lot cheaper and this overall improves performance?

[tbaederr]

Can you elaborate in your summary.

I am guessing because the other checks are a lot cheaper and this overall improves performance?

Yep. Updated the description.

[shafik]

LGTM