[llvm-exegesis][X86] Handle CMOVcc/SETcc OPERAND_COND_CODE OperandType

Summary:
D60041 / D60138 refactoring changed how CMOV/SETcc opcodes
are handled. concode is now an immediate, with it's own operand type.

This at least allows to not crash on the opcode.
However, this still won't generate all the snippets
with all the condcode enumerators. D60066 does that.

Reviewers: courbet, gchatelet

Reviewed By: gchatelet

Subscribers: tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60057

llvm-svn: 357841

test/tools/llvm-exegesis/X86/latency-CMOV32rr.s

@@ -0,0 +1,9 @@
+# RUN: llvm-exegesis -mode=latency -opcode-name=CMOV32rr | FileCheck %s
+
+CHECK:      ---
+CHECK-NEXT: mode: latency
+CHECK-NEXT: key:
+CHECK-NEXT:   instructions:
+CHECK-NEXT:     CMOV32rr
+CHECK-NEXT: config: ''
+CHECK-LAST: ...

tools/llvm-exegesis/lib/SnippetGenerator.cpp

@@ -12,6 +12,7 @@
 #include "Assembler.h"
 #include "MCInstrDescView.h"
 #include "SnippetGenerator.h"
+#include "Target.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Twine.h"
@@ -50,7 +51,7 @@ SnippetGenerator::generateConfigurations(const Instruction &Instr) const {
         BenchmarkCode BC;
         BC.Info = CT.Info;
         for (InstructionTemplate &IT : CT.Instructions) {
-          randomizeUnsetVariables(ForbiddenRegs, IT);
+          randomizeUnsetVariables(State.getExegesisTarget(), ForbiddenRegs, IT);
           BC.Instructions.push_back(IT.build());
         }
         if (CT.ScratchSpacePointerInReg)
@@ -156,29 +157,6 @@ static auto randomElement(const C &Container) -> decltype(Container[0]) {
   return Container[randomIndex(Container.size())];
 }
 
-static void randomize(const Instruction &Instr, const Variable &Var,
-                      llvm::MCOperand &AssignedValue,
-                      const llvm::BitVector &ForbiddenRegs) {
-  const Operand &Op = Instr.getPrimaryOperand(Var);
-  switch (Op.getExplicitOperandInfo().OperandType) {
-  case llvm::MCOI::OperandType::OPERAND_IMMEDIATE:
-    // FIXME: explore immediate values too.
-    AssignedValue = llvm::MCOperand::createImm(1);
-    break;
-  case llvm::MCOI::OperandType::OPERAND_REGISTER: {
-    assert(Op.isReg());
-    auto AllowedRegs = Op.getRegisterAliasing().sourceBits();
-    assert(AllowedRegs.size() == ForbiddenRegs.size());
-    for (auto I : ForbiddenRegs.set_bits())
-      AllowedRegs.reset(I);
-    AssignedValue = llvm::MCOperand::createReg(randomBit(AllowedRegs));
-    break;
-  }
-  default:
-    break;
-  }
-}
-
 static void setRegisterOperandValue(const RegisterOperandAssignment &ROV,
                                     InstructionTemplate &IB) {
   assert(ROV.Op);
@@ -212,12 +190,13 @@ void setRandomAliasing(const AliasingConfigurations &AliasingConfigurations,
   setRegisterOperandValue(randomElement(RandomConf.Uses), UseIB);
 }
 
-void randomizeUnsetVariables(const llvm::BitVector &ForbiddenRegs,
+void randomizeUnsetVariables(const ExegesisTarget &Target,
+                             const llvm::BitVector &ForbiddenRegs,
                              InstructionTemplate &IT) {
   for (const Variable &Var : IT.Instr.Variables) {
     llvm::MCOperand &AssignedValue = IT.getValueFor(Var);
     if (!AssignedValue.isValid())
-      randomize(IT.Instr, Var, AssignedValue, ForbiddenRegs);
+      Target.randomizeMCOperand(IT.Instr, Var, AssignedValue, ForbiddenRegs);
   }
 }
 

tools/llvm-exegesis/lib/SnippetGenerator.h

@@ -88,7 +88,8 @@ void setRandomAliasing(const AliasingConfigurations &AliasingConfigurations,
 
 // Assigns a Random Value to all Variables in IT that are still Invalid.
 // Do not use any of the registers in `ForbiddenRegs`.
-void randomizeUnsetVariables(const llvm::BitVector &ForbiddenRegs,
+void randomizeUnsetVariables(const ExegesisTarget &Target,
+                             const llvm::BitVector &ForbiddenRegs,
                              InstructionTemplate &IT);
 
 } // namespace exegesis

tools/llvm-exegesis/lib/Target.cpp

@@ -86,6 +86,30 @@ ExegesisTarget::createUopsBenchmarkRunner(const LLVMState &State) const {
   return llvm::make_unique<UopsBenchmarkRunner>(State);
 }
 
+void ExegesisTarget::randomizeMCOperand(
+    const Instruction &Instr, const Variable &Var,
+    llvm::MCOperand &AssignedValue,
+    const llvm::BitVector &ForbiddenRegs) const {
+  const Operand &Op = Instr.getPrimaryOperand(Var);
+  switch (Op.getExplicitOperandInfo().OperandType) {
+  case llvm::MCOI::OperandType::OPERAND_IMMEDIATE:
+    // FIXME: explore immediate values too.
+    AssignedValue = llvm::MCOperand::createImm(1);
+    break;
+  case llvm::MCOI::OperandType::OPERAND_REGISTER: {
+    assert(Op.isReg());
+    auto AllowedRegs = Op.getRegisterAliasing().sourceBits();
+    assert(AllowedRegs.size() == ForbiddenRegs.size());
+    for (auto I : ForbiddenRegs.set_bits())
+      AllowedRegs.reset(I);
+    AssignedValue = llvm::MCOperand::createReg(randomBit(AllowedRegs));
+    break;
+  }
+  default:
+    break;
+  }
+}
+
 static_assert(std::is_pod<PfmCountersInfo>::value,
               "We shouldn't have dynamic initialization here");
 const PfmCountersInfo PfmCountersInfo::Default = {nullptr, nullptr, nullptr,

tools/llvm-exegesis/lib/Target.h

@@ -102,6 +102,14 @@ public:
   // matter as long as it's large enough.
   virtual unsigned getMaxMemoryAccessSize() const { return 0; }
 
+  // Assigns a random operand of the right type to variable Var.
+  // The default implementation only handles generic operand types.
+  // The target is responsible for handling any operand
+  // starting from OPERAND_FIRST_TARGET.
+  virtual void randomizeMCOperand(const Instruction &Instr, const Variable &Var,
+                                  llvm::MCOperand &AssignedValue,
+                                  const llvm::BitVector &ForbiddenRegs) const;
+
   // Creates a snippet generator for the given mode.
   std::unique_ptr<SnippetGenerator>
   createSnippetGenerator(InstructionBenchmark::ModeE Mode,

tools/llvm-exegesis/lib/X86/Target.cpp

@@ -433,6 +433,10 @@ private:
 
   unsigned getMaxMemoryAccessSize() const override { return 64; }
 
+  void randomizeMCOperand(const Instruction &Instr, const Variable &Var,
+                          llvm::MCOperand &AssignedValue,
+                          const llvm::BitVector &ForbiddenRegs) const override;
+
   void fillMemoryOperands(InstructionTemplate &IT, unsigned Reg,
                           unsigned Offset) const override;
 
@@ -485,6 +489,23 @@ ExegesisX86Target::getScratchMemoryRegister(const llvm::Triple &TT) const {
   return TT.isOSWindows() ? llvm::X86::RCX : llvm::X86::RDI;
 }
 
+void ExegesisX86Target::randomizeMCOperand(
+    const Instruction &Instr, const Variable &Var,
+    llvm::MCOperand &AssignedValue,
+    const llvm::BitVector &ForbiddenRegs) const {
+  ExegesisTarget::randomizeMCOperand(Instr, Var, AssignedValue, ForbiddenRegs);
+
+  const Operand &Op = Instr.getPrimaryOperand(Var);
+  switch (Op.getExplicitOperandInfo().OperandType) {
+  case llvm::X86::OperandType::OPERAND_COND_CODE:
+    // FIXME: explore all CC variants.
+    AssignedValue = llvm::MCOperand::createImm(1);
+    break;
+  default:
+    break;
+  }
+}
+
 void ExegesisX86Target::fillMemoryOperands(InstructionTemplate &IT,
                                            unsigned Reg,
                                            unsigned Offset) const {