[llvm] [Analysis] Avoid running transform passes that have just been run (PR #112092)

[Arthur Eubanks via llvm-commits]

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@@ -5538,8 +5539,15 @@ void InstCombinePass::printPipeline(
   OS << '>';
 }
 
+char InstCombinePass::ID = 0;
+
 PreservedAnalyses InstCombinePass::run(Function &F,
                                        FunctionAnalysisManager &AM) {
+  auto &LRT = AM.getResult<LastRunTrackingAnalysis>(F);
+  // No changes since last InstCombine pass, exit early.
+  if (LRT.shouldSkip(&ID, Options))
+    return PreservedAnalyses::all();
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aeubanks wrote:

in the legacy pass manager, analyses were special passes. in the new pass manager, analyses and passes are separate concepts, so that sort of hack doesn't really work. and that doesn't solve the pass parameter issue.

https://github.com/llvm/llvm-project/pull/112092