[AsmPrinter] Remove hidden flag -print-schedule.

This patch removes hidden codegen flag -print-schedule effectively reverting the
logic originally committed as r300311
(https://llvm.org/viewvc/llvm-project?view=revision&revision=300311).

Flag -print-schedule was originally introduced by r300311 to address PR32216
(https://bugs.llvm.org/show_bug.cgi?id=32216). That bug was about adding "Better
testing of schedule model instruction latencies/throughputs".

These days, we can use llvm-mca to test scheduling models. So there is no longer
a need for flag -print-schedule in LLVM. The main use case for PR32216 is
now addressed by llvm-mca.
Flag -print-schedule is mainly used for debugging purposes, and it is only
actually used by x86 specific tests. We already have extensive (latency and
throughput) tests under "test/tools/llvm-mca" for X86 processor models. That
means, most (if not all) existing -print-schedule tests for X86 are redundant.

When flag -print-schedule was first added to LLVM, several files had to be
modified; a few APIs gained new arguments (see for example method
MCAsmStreamer::EmitInstruction), and MCSubtargetInfo/TargetSubtargetInfo gained
a couple of getSchedInfoStr() methods.

Method getSchedInfoStr() had to originally work for both MCInst and
MachineInstr. The original implmentation of getSchedInfoStr() introduced a
subtle layering violation (reported as PR37160 and then fixed/worked-around by
r330615).
In retrospect, that new API could have been designed more optimally. We can
always query MCSchedModel to get the latency and throughput. More importantly,
the "sched-info" string should not have been generated by the subtarget.
Note, r317782 fixed an issue where "print-schedule" didn't work very well in the
presence of inline assembly. That commit is also reverted by this change.

Differential Revision: https://reviews.llvm.org/D57244

llvm-svn: 353043

6 files changed, 2 insertions, 26 deletions

diff --git a/llvm/include/llvm/CodeGen/AsmPrinter.h b/llvm/include/llvm/CodeGen/AsmPrinter.h
index 4297450546a..fb12bb26b3e 100644
--- a/llvm/include/llvm/CodeGen/AsmPrinter.h
+++ b/llvm/include/llvm/CodeGen/AsmPrinter.h
@@ -121,9 +121,6 @@ public:
   using GOTEquivUsePair = std::pair<const GlobalVariable *, unsigned>;
   MapVector<const MCSymbol *, GOTEquivUsePair> GlobalGOTEquivs;
 
-  /// Enable print [latency:throughput] in output.
-  bool EnablePrintSchedInfo = false;
-
 private:
   MCSymbol *CurrentFnBegin = nullptr;
   MCSymbol *CurrentFnEnd = nullptr;
diff --git a/llvm/include/llvm/CodeGen/TargetSubtargetInfo.h b/llvm/include/llvm/CodeGen/TargetSubtargetInfo.h
index b206cf4e895..bf0e9b20833 100644
--- a/llvm/include/llvm/CodeGen/TargetSubtargetInfo.h
+++ b/llvm/include/llvm/CodeGen/TargetSubtargetInfo.h
@@ -189,9 +189,6 @@ public:
   /// TargetLowering preference). It does not yet disable the postRA scheduler.
   virtual bool enableMachineScheduler() const;
 
-  /// Support printing of [latency:throughput] comment in output .S file.
-  virtual bool supportPrintSchedInfo() const { return false; }
-
   /// True if the machine scheduler should disable the TLI preference
   /// for preRA scheduling with the source level scheduler.
   virtual bool enableMachineSchedDefaultSched() const { return true; }
@@ -285,10 +282,6 @@ public:
   /// possible.
   virtual bool enableSubRegLiveness() const { return false; }
 
-  /// Returns string representation of scheduler comment
-  std::string getSchedInfoStr(const MachineInstr &MI) const;
-  std::string getSchedInfoStr(MCInst const &MCI) const override;
-
   /// This is called after a .mir file was loaded.
   virtual void mirFileLoaded(MachineFunction &MF) const;
 };
diff --git a/llvm/include/llvm/MC/MCObjectStreamer.h b/llvm/include/llvm/MC/MCObjectStreamer.h
index 07d0ce68336..8affca49490 100644
--- a/llvm/include/llvm/MC/MCObjectStreamer.h
+++ b/llvm/include/llvm/MC/MCObjectStreamer.h
@@ -115,8 +115,7 @@ public:
   void EmitSLEB128Value(const MCExpr *Value) override;
   void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override;
   void ChangeSection(MCSection *Section, const MCExpr *Subsection) override;
-  void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
-                       bool = false) override;
+  void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
 
   /// Emit an instruction to a special fragment, because this instruction
   /// can change its size during relaxation.
diff --git a/llvm/include/llvm/MC/MCParser/MCAsmParser.h b/llvm/include/llvm/MC/MCParser/MCAsmParser.h
index d65347ab980..da5653ee71d 100644
--- a/llvm/include/llvm/MC/MCParser/MCAsmParser.h
+++ b/llvm/include/llvm/MC/MCParser/MCAsmParser.h
@@ -129,9 +129,6 @@ protected: // Can only create subclasses.
   /// Flag tracking whether any errors have been encountered.
   bool HadError = false;
 
-  /// Enable print [latency:throughput] in output file.
-  bool EnablePrintSchedInfo = false;
-
   bool ShowParsedOperands = false;
 
 public:
@@ -165,9 +162,6 @@ public:
   bool getShowParsedOperands() const { return ShowParsedOperands; }
   void setShowParsedOperands(bool Value) { ShowParsedOperands = Value; }
 
-  void setEnablePrintSchedInfo(bool Value) { EnablePrintSchedInfo = Value; }
-  bool shouldPrintSchedInfo() const { return EnablePrintSchedInfo; }
-
   /// Run the parser on the input source buffer.
   virtual bool Run(bool NoInitialTextSection, bool NoFinalize = false) = 0;
 
diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index 57514bebe12..dc2386fca85 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -952,9 +952,7 @@ public:
   virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
 
   /// Emit the given \p Instruction into the current section.
-  /// PrintSchedInfo == true then schedul comment should be added to output
-  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
-                               bool PrintSchedInfo = false);
+  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
 
   /// Set the bundle alignment mode from now on in the section.
   /// The argument is the power of 2 to which the alignment is set. The
diff --git a/llvm/include/llvm/MC/MCSubtargetInfo.h b/llvm/include/llvm/MC/MCSubtargetInfo.h
index 2ad72c3c325..c7472a28c77 100644
--- a/llvm/include/llvm/MC/MCSubtargetInfo.h
+++ b/llvm/include/llvm/MC/MCSubtargetInfo.h
@@ -180,11 +180,6 @@ public:
     auto Found = std::lower_bound(ProcDesc.begin(), ProcDesc.end(), CPU);
     return Found != ProcDesc.end() && StringRef(Found->Key) == CPU;
   }
-
-  /// Returns string representation of scheduler comment
-  virtual std::string getSchedInfoStr(MCInst const &MCI) const {
-    return {};
-  }
 };
 
 } // end namespace llvm