Author: Michael Maitland Date: 2025-01-24T23:42:18-05:00 New Revision: a41ded832d91141939c1b4aa2e955471a1047755
URL: https://github.com/llvm/llvm-project/commit/a41ded832d91141939c1b4aa2e955471a1047755 DIFF: https://github.com/llvm/llvm-project/commit/a41ded832d91141939c1b4aa2e955471a1047755.diff LOG: Revert "[GlobalMerge][NFC] Skip sorting by profitability when it is not neede…" This reverts commit e5e55c04d6af4ae32c99d574f59e632595abf607. Added: Modified: llvm/lib/CodeGen/GlobalMerge.cpp Removed: ################################################################################ diff --git a/llvm/lib/CodeGen/GlobalMerge.cpp b/llvm/lib/CodeGen/GlobalMerge.cpp index 41e01a1d3ccd52..7b76155b175d1d 100644 --- a/llvm/lib/CodeGen/GlobalMerge.cpp +++ b/llvm/lib/CodeGen/GlobalMerge.cpp @@ -423,12 +423,24 @@ bool GlobalMergeImpl::doMerge(SmallVectorImpl<GlobalVariable *> &Globals, } } + // Now we found a bunch of sets of globals used together. We accumulated + // the number of times we encountered the sets (i.e., the number of functions + // that use that exact set of globals). + // + // Multiply that by the size of the set to give us a crude profitability + // metric. + llvm::stable_sort(UsedGlobalSets, + [](const UsedGlobalSet &UGS1, const UsedGlobalSet &UGS2) { + return UGS1.Globals.count() * UGS1.UsageCount < + UGS2.Globals.count() * UGS2.UsageCount; + }); + // We can choose to merge all globals together, but ignore globals never used // with another global. This catches the obviously non-profitable cases of // having a single global, but is aggressive enough for any other case. if (GlobalMergeIgnoreSingleUse) { BitVector AllGlobals(Globals.size()); - for (const UsedGlobalSet &UGS : UsedGlobalSets) { + for (const UsedGlobalSet &UGS : llvm::reverse(UsedGlobalSets)) { if (UGS.UsageCount == 0) continue; if (UGS.Globals.count() > 1) @@ -437,16 +449,6 @@ bool GlobalMergeImpl::doMerge(SmallVectorImpl<GlobalVariable *> &Globals, return doMerge(Globals, AllGlobals, M, isConst, AddrSpace); } - // Now we found a bunch of sets of globals used together. We accumulated - // the number of times we encountered the sets (i.e., the number of functions - // that use that exact set of globals). Multiply that by the size of the set - // to give us a crude profitability metric. - llvm::stable_sort(UsedGlobalSets, - [](const UsedGlobalSet &UGS1, const UsedGlobalSet &UGS2) { - return UGS1.Globals.count() * UGS1.UsageCount >= - UGS2.Globals.count() * UGS2.UsageCount; - }); - // Starting from the sets with the best (=biggest) profitability, find a // good combination. // The ideal (and expensive) solution can only be found by trying all @@ -456,7 +458,7 @@ bool GlobalMergeImpl::doMerge(SmallVectorImpl<GlobalVariable *> &Globals, BitVector PickedGlobals(Globals.size()); bool Changed = false; - for (const UsedGlobalSet &UGS : UsedGlobalSets) { + for (const UsedGlobalSet &UGS : llvm::reverse(UsedGlobalSets)) { if (UGS.UsageCount == 0) continue; if (PickedGlobals.anyCommon(UGS.Globals)) _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
