MIR Serialization: Serialize the frame info's save and restore points.

This commit serializes the save and restore machine basic block references from
the machine frame information class.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243575 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MIRYamlMapping.h

@@ -326,7 +326,8 @@ struct MachineFrameInfo {
   bool HasOpaqueSPAdjustment = false;
   bool HasVAStart = false;
   bool HasMustTailInVarArgFunc = false;
-  // TODO: Serialize save and restore MBB references.
+  StringValue SavePoint;
+  StringValue RestorePoint;
 };
 
 template <> struct MappingTraits<MachineFrameInfo> {
@@ -344,6 +345,10 @@ template <> struct MappingTraits<MachineFrameInfo> {
     YamlIO.mapOptional("hasOpaqueSPAdjustment", MFI.HasOpaqueSPAdjustment);
     YamlIO.mapOptional("hasVAStart", MFI.HasVAStart);
     YamlIO.mapOptional("hasMustTailInVarArgFunc", MFI.HasMustTailInVarArgFunc);
+    YamlIO.mapOptional("savePoint", MFI.SavePoint,
+                       StringValue()); // Don't print it out when it's empty.
+    YamlIO.mapOptional("restorePoint", MFI.RestorePoint,
+                       StringValue()); // Don't print it out when it's empty.
   }
 };
 

lib/CodeGen/MIRParser/MIRParser.cpp

@@ -282,8 +282,6 @@ bool MIRParserImpl::initializeMachineFunction(MachineFunction &MF) {
   PerFunctionMIParsingState PFS;
   if (initializeRegisterInfo(MF, YamlMF, PFS))
     return true;
-  if (initializeFrameInfo(MF, YamlMF, PFS))
-    return true;
   if (!YamlMF.Constants.empty()) {
     auto *ConstantPool = MF.getConstantPool();
     assert(ConstantPool && "Constant pool must be created");
@@ -324,6 +322,10 @@ bool MIRParserImpl::initializeMachineFunction(MachineFunction &MF) {
   if (YamlMF.BasicBlocks.empty())
     return error(Twine("machine function '") + Twine(MF.getName()) +
                  "' requires at least one machine basic block in its body");
+  // Initialize the frame information after creating all the MBBs so that the
+  // MBB references in the frame information can be resolved.
+  if (initializeFrameInfo(MF, YamlMF, PFS))
+    return true;
   // Initialize the jump table after creating all the MBBs so that the MBB
   // references can be resolved.
   if (!YamlMF.JumpTableInfo.Entries.empty() &&
@@ -450,6 +452,18 @@ bool MIRParserImpl::initializeFrameInfo(MachineFunction &MF,
   MFI.setHasOpaqueSPAdjustment(YamlMFI.HasOpaqueSPAdjustment);
   MFI.setHasVAStart(YamlMFI.HasVAStart);
   MFI.setHasMustTailInVarArgFunc(YamlMFI.HasMustTailInVarArgFunc);
+  if (!YamlMFI.SavePoint.Value.empty()) {
+    MachineBasicBlock *MBB = nullptr;
+    if (parseMBBReference(MBB, YamlMFI.SavePoint, MF, PFS))
+      return true;
+    MFI.setSavePoint(MBB);
+  }
+  if (!YamlMFI.RestorePoint.Value.empty()) {
+    MachineBasicBlock *MBB = nullptr;
+    if (parseMBBReference(MBB, YamlMFI.RestorePoint, MF, PFS))
+      return true;
+    MFI.setRestorePoint(MBB);
+  }
 
   std::vector<CalleeSavedInfo> CSIInfo;
   // Initialize the fixed frame objects.

lib/CodeGen/MIRPrinter.cpp

@@ -72,7 +72,8 @@ public:
 
   void convert(yaml::MachineFunction &MF, const MachineRegisterInfo &RegInfo,
                const TargetRegisterInfo *TRI);
-  void convert(yaml::MachineFrameInfo &YamlMFI, const MachineFrameInfo &MFI);
+  void convert(ModuleSlotTracker &MST, yaml::MachineFrameInfo &YamlMFI,
+               const MachineFrameInfo &MFI);
   void convert(yaml::MachineFunction &MF,
                const MachineConstantPool &ConstantPool);
   void convert(ModuleSlotTracker &MST, yaml::MachineJumpTable &YamlJTI,
@@ -158,14 +159,13 @@ void MIRPrinter::print(const MachineFunction &MF) {
   YamlMF.ExposesReturnsTwice = MF.exposesReturnsTwice();
   YamlMF.HasInlineAsm = MF.hasInlineAsm();
   convert(YamlMF, MF.getRegInfo(), MF.getSubtarget().getRegisterInfo());
-  convert(YamlMF.FrameInfo, *MF.getFrameInfo());
+  ModuleSlotTracker MST(MF.getFunction()->getParent());
+  MST.incorporateFunction(*MF.getFunction());
+  convert(MST, YamlMF.FrameInfo, *MF.getFrameInfo());
   convertStackObjects(YamlMF, *MF.getFrameInfo(),
                       MF.getSubtarget().getRegisterInfo());
   if (const auto *ConstantPool = MF.getConstantPool())
     convert(YamlMF, *ConstantPool);
-
-  ModuleSlotTracker MST(MF.getFunction()->getParent());
-  MST.incorporateFunction(*MF.getFunction());
   if (const auto *JumpTableInfo = MF.getJumpTableInfo())
     convert(MST, YamlMF.JumpTableInfo, *JumpTableInfo);
   for (const auto &MBB : MF) {
@@ -207,7 +207,8 @@ void MIRPrinter::convert(yaml::MachineFunction &MF,
   }
 }
 
-void MIRPrinter::convert(yaml::MachineFrameInfo &YamlMFI,
+void MIRPrinter::convert(ModuleSlotTracker &MST,
+                         yaml::MachineFrameInfo &YamlMFI,
                          const MachineFrameInfo &MFI) {
   YamlMFI.IsFrameAddressTaken = MFI.isFrameAddressTaken();
   YamlMFI.IsReturnAddressTaken = MFI.isReturnAddressTaken();
@@ -222,6 +223,16 @@ void MIRPrinter::convert(yaml::MachineFrameInfo &YamlMFI,
   YamlMFI.HasOpaqueSPAdjustment = MFI.hasOpaqueSPAdjustment();
   YamlMFI.HasVAStart = MFI.hasVAStart();
   YamlMFI.HasMustTailInVarArgFunc = MFI.hasMustTailInVarArgFunc();
+  if (MFI.getSavePoint()) {
+    raw_string_ostream StrOS(YamlMFI.SavePoint.Value);
+    MIPrinter(StrOS, MST, RegisterMaskIds, StackObjectOperandMapping)
+        .printMBBReference(*MFI.getSavePoint());
+  }
+  if (MFI.getRestorePoint()) {
+    raw_string_ostream StrOS(YamlMFI.RestorePoint.Value);
+    MIPrinter(StrOS, MST, RegisterMaskIds, StackObjectOperandMapping)
+        .printMBBReference(*MFI.getRestorePoint());
+  }
 }
 
 void MIRPrinter::convertStackObjects(yaml::MachineFunction &MF,

test/CodeGen/MIR/X86/frame-info-save-restore-points.mir

@@ -0,0 +1,72 @@
+# RUN: llc -march=x86-64 -enable-shrink-wrap=true -start-after shrink-wrap -stop-after shrink-wrap -o /dev/null %s | FileCheck %s
+# This test ensures that the MIR parser parses the save and restore points in
+# the machine frame info correctly.
+
+--- |
+
+  define i32 @foo(i32 %a, i32 %b) {
+  entry:
+    %tmp = alloca i32, align 4
+    %tmp2 = icmp slt i32 %a, %b
+    br i1 %tmp2, label %true, label %false
+
+  true:
+    store i32 %a, i32* %tmp, align 4
+    %tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
+    br label %false
+
+  false:
+    %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %entry ]
+    ret i32 %tmp.0
+  }
+
+  declare i32 @doSomething(i32, i32*)
+
+...
+---
+name:            foo
+tracksRegLiveness: true
+liveins:
+  - { reg: '%edi' }
+  - { reg: '%esi' }
+# CHECK: frameInfo:
+# CHECK:      savePoint: '%bb.2.true'
+# CHECK-NEXT: restorePoint: '%bb.2.true'
+# CHECK: stack
+frameInfo:
+  maxAlignment:  4
+  hasCalls:      true
+  savePoint:     '%bb.2.true'
+  restorePoint:  '%bb.2.true'
+stack:
+  - { id: 0, name: tmp, offset: 0, size: 4, alignment: 4 }
+body:
+  - id:          0
+    successors:  [ '%bb.2.true', '%bb.1' ]
+    liveins:     [ '%edi', '%esi' ]
+    instructions:
+      - '%eax = COPY %edi'
+      - 'CMP32rr %eax, killed %esi, implicit-def %eflags'
+      - 'JL_1 %bb.2.true, implicit killed %eflags'
+  - id:          1
+    successors:  [ '%bb.3.false' ]
+    liveins:     [ '%eax' ]
+    instructions:
+      - 'JMP_1 %bb.3.false'
+  - id:          2
+    name:        'true'
+    successors:  [ '%bb.3.false' ]
+    liveins:     [ '%eax' ]
+    instructions:
+      - 'MOV32mr %stack.0.tmp, 1, _, 0, _, killed %eax'
+      - 'ADJCALLSTACKDOWN64 0, 0, implicit-def %rsp, implicit-def dead %eflags, implicit %rsp'
+      - '%rsi = LEA64r %stack.0.tmp, 1, _, 0, _'
+      - '%edi = MOV32r0 implicit-def dead %eflags'
+      - 'CALL64pcrel32 @doSomething, csr_64, implicit %rsp, implicit %edi, implicit %rsi, implicit-def %rsp, implicit-def %eax'
+      - 'ADJCALLSTACKUP64 0, 0, implicit-def %rsp, implicit-def dead %eflags, implicit %rsp'
+  - id:          3
+    name:        'false'
+    liveins:     [ '%eax' ]
+    instructions:
+      - 'RETQ %eax'
+...