[llvm] r305245 - Inliner: Don't remove calls to readnone+nounwind (but not always_inline) functions in the AlwaysInliner

Thu Jun 15 04:02:07 PDT 2017

Hi David,

With this commit, opt crashes when doing:

opt -S -functionattrs -inline -instcombine -o - callgraph.ll

opt: ../include/llvm/Analysis/CallGraph.h:174: 
llvm::CallGraphNode::~CallGraphNode(): Assertion `NumReferences == 0 && 
"Node deleted while references remain"' failed.

Regards,
Mikael

On 06/13/2017 01:01 AM, David Blaikie via llvm-commits wrote:
> Author: dblaikie
> Date: Mon Jun 12 18:01:17 2017
> New Revision: 305245
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=305245&view=rev
> Log:
> Inliner: Don't remove calls to readnone+nounwind (but not always_inline) functions in the AlwaysInliner
> 
> Modified:
>      llvm/trunk/lib/Transforms/IPO/Inliner.cpp
>      llvm/trunk/test/Transforms/Inline/always-inline.ll
> 
> Modified: llvm/trunk/lib/Transforms/IPO/Inliner.cpp
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/Inliner.cpp?rev=305245&r1=305244&r2=305245&view=diff
> ==============================================================================
> --- llvm/trunk/lib/Transforms/IPO/Inliner.cpp (original)
> +++ llvm/trunk/lib/Transforms/IPO/Inliner.cpp Mon Jun 12 18:01:17 2017
> @@ -523,6 +523,16 @@ inlineCallsImpl(CallGraphSCC &SCC, CallG
>         if (!Callee || Callee->isDeclaration())
>           continue;
>   
> +      // FIXME for new PM: because of the old PM we currently generate ORE and
> +      // in turn BFI on demand.  With the new PM, the ORE dependency should
> +      // just become a regular analysis dependency.
> +      OptimizationRemarkEmitter ORE(Caller);
> +
> +      // If the policy determines that we should inline this function,
> +      // delete the call instead.
> +      if (!shouldInline(CS, GetInlineCost, ORE))
> +        continue;
> +
>         // If this call site is dead and it is to a readonly function, we should
>         // just delete the call instead of trying to inline it, regardless of
>         // size.  This happens because IPSCCP propagates the result out of the
> @@ -548,15 +558,6 @@ inlineCallsImpl(CallGraphSCC &SCC, CallG
>           // Get DebugLoc to report. CS will be invalid after Inliner.
>           DebugLoc DLoc = CS.getInstruction()->getDebugLoc();
>           BasicBlock *Block = CS.getParent();
> -        // FIXME for new PM: because of the old PM we currently generate ORE and
> -        // in turn BFI on demand.  With the new PM, the ORE dependency should
> -        // just become a regular analysis dependency.
> -        OptimizationRemarkEmitter ORE(Caller);
> -
> -        // If the policy determines that we should inline this function,
> -        // try to do so.
> -        if (!shouldInline(CS, GetInlineCost, ORE))
> -          continue;
>   
>           // Attempt to inline the function.
>           using namespace ore;
> 
> Modified: llvm/trunk/test/Transforms/Inline/always-inline.ll
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/Inline/always-inline.ll?rev=305245&r1=305244&r2=305245&view=diff
> ==============================================================================
> --- llvm/trunk/test/Transforms/Inline/always-inline.ll (original)
> +++ llvm/trunk/test/Transforms/Inline/always-inline.ll Mon Jun 12 18:01:17 2017
> @@ -305,3 +305,14 @@ entry:
>     ret void
>   ; CHECK: ret void
>   }
> +
> +define void @inner14() readnone nounwind {
> +; CHECK: define void @inner14
> +  ret void
> +}
> +
> +define void @outer14() {
> +; CHECK: call void @inner14
> +  call void @inner14()
> +  ret void
> +}
> 
> 
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at lists.llvm.org
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> 
-------------- next part --------------
; ModuleID = 'bugpoint-reduced-simplified.bc'
; source_filename = "bugpoint-output-7c2cf05.bc"
; target datalayout = "E-B16-p:16:16-p21:32:16-p40:32:16-F40-i1:16-i8:16-i32:16-i64:16-f32:16-f64:16-v32:16:16-v64:16:16-v128:16:16-a:0:16-i24:16-i40:16-n16:32"
; target triple = "phoenix"

; opt -S -functionattrs -inline -instcombine -o - 

%struct.a.0.4.8.12.16.20.24.28.32.36 = type { i16, i16 }
%struct.b.1.5.9.13.17.21.25.29.33.37 = type { i16, i16 }
%struct._bbiMcs_pageS.2.6.10.14.18.22.26.30.34.38 = type { i16, i16, i16 }
%struct._BbiMcs_pageS.3.7.11.15.19.23.27.31.35.39 = type { i16, i16 }

@i = external addrspace(21) global %struct.a.0.4.8.12.16.20.24.28.32.36, align 1

; Function Attrs: noinline nounwind
declare %struct.a.0.4.8.12.16.20.24.28.32.36 addrspace(21)* @foo() #0

; Function Attrs: noinline nounwind
define %struct.b.1.5.9.13.17.21.25.29.33.37 addrspace(21)* @bar() #0 {
entry:
  ret %struct.b.1.5.9.13.17.21.25.29.33.37 addrspace(21)* undef
}

; Function Attrs: noinline nounwind
define %struct._bbiMcs_pageS.2.6.10.14.18.22.26.30.34.38 addrspace(21)* @bbiMcs_getPageAddr() #0 {
entry:
  %call = call %struct._BbiMcs_pageS.3.7.11.15.19.23.27.31.35.39 addrspace(21)* @bbiMcs_cmAddr()
  ret %struct._bbiMcs_pageS.2.6.10.14.18.22.26.30.34.38 addrspace(21)* undef
}

; Function Attrs: noinline nounwind
declare i16 @main(i16, i16**) #0

; Function Attrs: noinline nounwind
define internal %struct._BbiMcs_pageS.3.7.11.15.19.23.27.31.35.39 addrspace(21)* @bbiMcs_cmAddr() #0 {
entry:
  ret %struct._BbiMcs_pageS.3.7.11.15.19.23.27.31.35.39 addrspace(21)* inttoptr (i32 4660 to %struct._BbiMcs_pageS.3.7.11.15.19.23.27.31.35.39 addrspace(21)*)
}

attributes #0 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="phoenixIII" "unsafe-fp-math"="false" "use-soft-float"="false" }

!llvm.ident = !{!0}

!0 = !{!"clang version 5.0.0  (FLACC_FADER_6.64-1146-g84bf040774)"}