[flang-commits] [flang] [flang] Added LoopInvariantCodeMotion pass for [HL]FIR. (PR #173438)

[Tom Eccles via flang-commits]

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@@ -206,6 +206,10 @@ void createDefaultFIROptimizerPassPipeline(mlir::PassManager &pm,
   pm.addPass(fir::createSimplifyRegionLite());
   pm.addPass(mlir::createCSEPass());
 
+  // Run LICM after CSE, which may reduce the number of operations to hoist.
+  if (pc.OptLevel.isOptimizingForSpeed())
+    pm.addPass(fir::createLoopInvariantCodeMotion());
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tblah wrote:

Thanks.

I'm not really opposed to having this on by default so long as you don't find serious compilation time regressions (I agree this pass looks useful in the long term), but feel free to disable by default for now if you prefer.

https://github.com/llvm/llvm-project/pull/173438