New case of "VPlan cost model and legacy cost model disagreed" #158660
Description
Our testing encountered a new regression which bisects to 91d4c0d (tag @fhahn ).
Let me know if you need any more info!
https://godbolt.org/z/r4qo3e9fs
target triple = "x86_64-unknown-unknown"
; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.usub.sat.i32(i32, i32) #0
define i64 @baz(i32 %arg, i1 %arg1) #1 {
bb:
br label %bb3
bb2: ; preds = %bb5
ret i64 %phi6
bb3: ; preds = %bb5, %bb
%phi = phi i32 [ 0, %bb ], [ %add, %bb5 ]
br i1 %arg1, label %bb5, label %bb4
bb4: ; preds = %bb3
%call = tail call i32 @llvm.usub.sat.i32(i32 %phi, i32 1)
%udiv = udiv i32 %call, %arg
%zext = zext i32 %udiv to i64
br label %bb5
bb5: ; preds = %bb4, %bb3
%phi6 = phi i64 [ %zext, %bb4 ], [ 0, %bb3 ]
%add = add i32 %phi, 1
%icmp = icmp eq i32 %phi, %arg
br i1 %icmp, label %bb2, label %bb3
}
attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
attributes #1 = { "target-cpu"="znver2" }
opt: /root/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:7074: llvm::VectorizationFactor llvm::LoopVectorizationPlanner::computeBestVF(): Assertion `(BestFactor.Width == LegacyVF.Width || BestPlan.hasEarlyExit() || planContainsAdditionalSimplifications(getPlanFor(BestFactor.Width), CostCtx, OrigLoop, BestFactor.Width) || planContainsAdditionalSimplifications( getPlanFor(LegacyVF.Width), CostCtx, OrigLoop, LegacyVF.Width)) && " VPlan cost model and legacy cost model disagreed"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0. Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/opt -o /app/output.s -S --passes=loop-vectorize <source>
1. Running pass "function(loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>)" on module "<source>"
2. Running pass "loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>" on function "baz"
#0 0x00000000058a7268 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x58a7268)
#1 0x00000000058a4114 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
#2 0x0000710df7042520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
#3 0x0000710df70969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
#4 0x0000710df7042476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
#5 0x0000710df70287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
#6 0x0000710df702871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
#7 0x0000710df7039e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#8 0x000000000362ead6 llvm::LoopVectorizationPlanner::computeBestVF() (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x362ead6)
#9 0x000000000363c224 llvm::LoopVectorizePass::processLoop(llvm::Loop*) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x363c224)
#10 0x000000000363f420 llvm::LoopVectorizePass::runImpl(llvm::Function&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x363f420)
#11 0x000000000363fb05 llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x363fb05)
#12 0x0000000002f3816e llvm::detail::PassModel<llvm::Function, llvm::LoopVectorizePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x2f3816e)
#13 0x00000000056905d1 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x56905d1)
#14 0x0000000000eec31e llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0xeec31e)
#15 0x000000000568eb3a llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x568eb3a)
#16 0x000000000096f54e llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x96f54e)
#17 0x000000000568e4f1 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x568e4f1)
#18 0x0000000000979848 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x979848)
#19 0x000000000096d8c9 optMain (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x96d8c9)
#20 0x0000710df7029d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#21 0x0000710df7029e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#22 0x0000000000964a15 _start (/opt/compiler-explorer/clang-assertions-trunk/bin/opt+0x964a15)
Program terminated with signal: SIGSEGV
Compiler returned: 139