void ShortestPathAnalysis::analyzeLoopsRecursively(SILLoop *Loop, int LoopDepth) { if (LoopDepth >= MaxNumLoopLevels) return; // First dive into the inner loops. for (SILLoop *SubLoop : Loop->getSubLoops()) { analyzeLoopsRecursively(SubLoop, LoopDepth + 1); } BlockInfo *HeaderInfo = getBlockInfo(Loop->getHeader()); Distances &HeaderDists = HeaderInfo->getDistances(LoopDepth); // Initial values for the entry (== header) and exit-predecessor (== header as // well). HeaderDists.DistFromEntry = 0; HeaderDists.DistToExit = 0; solveDataFlow(Loop->getBlocks(), LoopDepth); int LoopLength = getExitDistFromSuccs(Loop->getHeader(), LoopDepth) + HeaderInfo->getLength(LoopDepth); HeaderDists.DistToExit = LoopLength; // If there is a loop bypass edge, add the loop length to the loop pre-pre- // header instead to the header. This actually let us ignore the loop bypass // edge in the length calculation for the loop's parent scope. if (SILBasicBlock *Bypass = detectLoopBypassPreheader(Loop)) HeaderInfo = getBlockInfo(Bypass); // Add the full loop length (= assumed-iteration-count * length) to the loop // header so that it is considered in the parent scope. HeaderInfo->getDistances(LoopDepth - 1).LoopHeaderLength = LoopCount * LoopLength; }