Fangrui Song c9829bfb08 [LazyCallGraph] Build SCCs of the reference graph in order ... ``` // The legacy PM CGPassManager discovers SCCs this way: for function in the source order tarjanSCC(function) // While the new PM CGSCCPassManager does: for function in the reversed source order [1] discover a reference graph SCC build call graph SCCs inside the reference graph SCC ``` In the common cases, reference graph ~= call graph, the new PM order is undesired because for `a | b | c` (3 independent functions), the new PM will process them in the reversed order: c, b, a. If `a <-> b <-> c`, we can see that `-print-after-all` will report the sole SCC as `scc: (c, b, a)`. This patch corrects the iteration order. The discovered SCC order will match the legacy PM in the common cases. For some tests (`Transforms/Inline/cgscc-*.ll` and `unittests/Analysis/CGSCCPassManagerTest.cpp`), the behaviors are dependent on the SCC discovery order and there are too many check lines for the particular order. This patch simply reverses the function order to avoid changing too many check lines. Differential Revision: https://reviews.llvm.org/D90566		2020-11-02 13:22:42 -08:00
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alias.ll	[LazyCallGraph] Build SCCs of the reference graph in order	2020-11-02 13:22:42 -08:00
basic.ll	[LazyCallGraph] Build SCCs of the reference graph in order	2020-11-02 13:22:42 -08:00
non-leaf-intrinsics.ll