-print-after-all banner not printed following r292442

[llvmbot]

Bugzilla Link	32207
Resolution	FIXED
Resolved on	Jun 11, 2017 19:18
Version	trunk
OS	All
Reporter	LLVM Bugzilla Contributor
CC	@joker-eph

Extended Description

$ cat a.cpp void foo() {} $ clang -c -O a.cpp -mllvm -print-after-all |& grep unused IR Dump After Remove unused exception handling info $ clang -c -O a.cpp -mllvm -print-after-all |& grep inlining $ clang -v clang version 5.0.0 (trunk 294982)

the problem is static bool BannerPrinted is shared across all PrintCallGraphPass passes so only the first pass (Remove unused exception handling info) prints its banner.

To achieve one BannerPrinted per non-empty SCC, it should be non static local to runOnSCC:

bool runOnSCC(CallGraphSCC &SCC) override {
  bool BannerPrinted = false;
  auto PrintBannerOnce = [&] () {
    if (BannerPrinted)
      return;
    Out << Banner;
    BannerPrinted = true;
    };
  for (CallGraphNode *CGN : SCC) {
    if (CGN->getFunction()) {
      if (isFunctionInPrintList(CGN->getFunction()->getName())) {
        PrintBannerOnce();
        CGN->getFunction()->print(Out);
      }
    } else if (llvm::isFunctionInPrintList("*")) {
      PrintBannerOnce();
      Out << "\nPrinting <null> Function\n";
    }
  }
  return false;
}

[llvmbot]

https://reviews.llvm.org/rL305179

[llvmbot]

https://reviews.llvm.org/D34086

[joker-eph]

Can you submit a patch?

[llvmbot]

ping...

[llvmbot]

Ping?

[llvmbot]

skipping declaration prints better:

bool runOnSCC(CallGraphSCC &SCC) override {
  bool BannerPrinted = false;
  auto PrintBannerOnce = [&] () {
    if (BannerPrinted)
      return;
    Out << Banner;
    BannerPrinted = true;
    };
  for (CallGraphNode *CGN : SCC) {
    if (Function *F = CGN->getFunction()) {
      if (!F->isDeclaration() && isFunctionInPrintList(F->getName())) {
        PrintBannerOnce();
        F->print(Out);
      }
    } else if (llvm::isFunctionInPrintList("*")) {
      PrintBannerOnce();
      Out << "\nPrinting <null> Function\n";
    }
  }
  return false;
}

[llvmbot]

scc (and the text output) are interleaved, all scc passes on scc1, all scc passes on scc2 etc. for example the output with this patch for two unrelated functions maind and foo is:

IR Dump After Remove unused exception handling info ; Function Attrs: norecurse nounwind uwtable define i32 @​main() #​0 !dbg !​7 { entry: ret i32 0, !dbg !​11 } IR Dump After Function Integration/Inlining ; Function Attrs: norecurse nounwind uwtable define i32 @​main() #​0 !dbg !​7 { entry: ret i32 0, !dbg !​11 }

...

IR Dump After Function Integration/Inlining ; Function Attrs: noreturn nounwind uwtable define i32 @​_Z3foov() #​1 !dbg !​7 { entry: unreachable, !dbg !​11 } IR Dump After Deduce function attributes ; Function Attrs: norecurse noreturn nounwind readnone uwtable define i32 @​_Z3foov() #​1 !dbg !​7 { entry: unreachable, !dbg !​11 } ...

runs are disjointed, can't merge the banners between scc prints.

[joker-eph]

Yep, that was a terrible patch I wrote there ;)

The issue is that the fix you suggest does not provide the feature I am looking for, which is have each PrintCallGraphPass print only once.

You change will make it print once per SCC. What do you think about making it a member variable of the CallGraphSCC class instead?