MachineFrameInfo: Track whether MaxCallFrameSize is computed yet; NFC

This tracks whether MaxCallFrameSize is computed yet. Ideally we would
assert and fail when the value is queried before it is computed, however
this fails various targets that need to be fixed first.

Differential Revision: https://reviews.llvm.org/D32570

llvm-svn: 301851

6 files changed, 17 insertions, 8 deletions

diff --git a/llvm/include/llvm/CodeGen/MIRYamlMapping.h b/llvm/include/llvm/CodeGen/MIRYamlMapping.h
index 38cf8aa165a..47b40de6fe1 100644
--- a/llvm/include/llvm/CodeGen/MIRYamlMapping.h
+++ b/llvm/include/llvm/CodeGen/MIRYamlMapping.h
@@ -345,7 +345,7 @@ struct MachineFrameInfo {
   bool HasCalls = false;
   StringValue StackProtector;
   // TODO: Serialize FunctionContextIdx
-  unsigned MaxCallFrameSize = 0;
+  unsigned MaxCallFrameSize = ~0u; ///< ~0u means: not computed yet.
   bool HasOpaqueSPAdjustment = false;
   bool HasVAStart = false;
   bool HasMustTailInVarArgFunc = false;
@@ -366,7 +366,7 @@ template <> struct MappingTraits<MachineFrameInfo> {
     YamlIO.mapOptional("hasCalls", MFI.HasCalls);
     YamlIO.mapOptional("stackProtector", MFI.StackProtector,
                        StringValue()); // Don't print it out when it's empty.
-    YamlIO.mapOptional("maxCallFrameSize", MFI.MaxCallFrameSize);
+    YamlIO.mapOptional("maxCallFrameSize", MFI.MaxCallFrameSize, ~0u);
     YamlIO.mapOptional("hasOpaqueSPAdjustment", MFI.HasOpaqueSPAdjustment);
     YamlIO.mapOptional("hasVAStart", MFI.HasVAStart);
     YamlIO.mapOptional("hasMustTailInVarArgFunc", MFI.HasMustTailInVarArgFunc);
diff --git a/llvm/include/llvm/CodeGen/MachineFrameInfo.h b/llvm/include/llvm/CodeGen/MachineFrameInfo.h
index a746689d953..61be9f775c9 100644
--- a/llvm/include/llvm/CodeGen/MachineFrameInfo.h
+++ b/llvm/include/llvm/CodeGen/MachineFrameInfo.h
@@ -220,7 +220,7 @@ class MachineFrameInfo {
   /// setup/destroy pseudo instructions (as defined in the TargetFrameInfo
   /// class).  This information is important for frame pointer elimination.
   /// It is only valid during and after prolog/epilog code insertion.
-  unsigned MaxCallFrameSize = 0;
+  unsigned MaxCallFrameSize = ~0u;
 
   /// The prolog/epilog code inserter fills in this vector with each
   /// callee saved register saved in the frame.  Beyond its use by the prolog/
@@ -525,7 +525,16 @@ public:
   /// CallFrameSetup/Destroy pseudo instructions are used by the target, and
   /// then only during or after prolog/epilog code insertion.
   ///
-  unsigned getMaxCallFrameSize() const { return MaxCallFrameSize; }
+  unsigned getMaxCallFrameSize() const {
+    // TODO: Enable this assert when targets are fixed.
+    //assert(isMaxCallFrameSizeComputed() && "MaxCallFrameSize not computed yet");
+    if (!isMaxCallFrameSizeComputed())
+      return 0;
+    return MaxCallFrameSize;
+  }
+  bool isMaxCallFrameSizeComputed() const {
+    return MaxCallFrameSize != ~0u;
+  }
   void setMaxCallFrameSize(unsigned S) { MaxCallFrameSize = S; }
 
   /// Create a new object at a fixed location on the stack.
diff --git a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
index a2773cccc5d..bd04acd049d 100644
--- a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
@@ -541,7 +541,8 @@ bool MIRParserImpl::initializeFrameInfo(PerFunctionMIParsingState &PFS,
     MFI.ensureMaxAlignment(YamlMFI.MaxAlignment);
   MFI.setAdjustsStack(YamlMFI.AdjustsStack);
   MFI.setHasCalls(YamlMFI.HasCalls);
-  MFI.setMaxCallFrameSize(YamlMFI.MaxCallFrameSize);
+  if (YamlMFI.MaxCallFrameSize != ~0u)
+    MFI.setMaxCallFrameSize(YamlMFI.MaxCallFrameSize);
   MFI.setHasOpaqueSPAdjustment(YamlMFI.HasOpaqueSPAdjustment);
   MFI.setHasVAStart(YamlMFI.HasVAStart);
   MFI.setHasMustTailInVarArgFunc(YamlMFI.HasMustTailInVarArgFunc);
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index b6624b88fe2..d017b21f0a5 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -286,7 +286,8 @@ void MIRPrinter::convert(ModuleSlotTracker &MST,
   YamlMFI.MaxAlignment = MFI.getMaxAlignment();
   YamlMFI.AdjustsStack = MFI.adjustsStack();
   YamlMFI.HasCalls = MFI.hasCalls();
-  YamlMFI.MaxCallFrameSize = MFI.getMaxCallFrameSize();
+  YamlMFI.MaxCallFrameSize = MFI.isMaxCallFrameSizeComputed()
+    ? MFI.getMaxCallFrameSize() : ~0u;
   YamlMFI.HasOpaqueSPAdjustment = MFI.hasOpaqueSPAdjustment();
   YamlMFI.HasVAStart = MFI.hasVAStart();
   YamlMFI.HasMustTailInVarArgFunc = MFI.hasMustTailInVarArgFunc();
diff --git a/llvm/test/CodeGen/MIR/Generic/frame-info.mir b/llvm/test/CodeGen/MIR/Generic/frame-info.mir
index 7c6e6ebbfee..157eb99e149 100644
--- a/llvm/test/CodeGen/MIR/Generic/frame-info.mir
+++ b/llvm/test/CodeGen/MIR/Generic/frame-info.mir
@@ -36,7 +36,6 @@ tracksRegLiveness: true
 # CHECK-NEXT: maxAlignment:
 # CHECK-NEXT: adjustsStack: false
 # CHECK-NEXT: hasCalls: false
-# CHECK-NEXT: maxCallFrameSize: 0
 # CHECK-NEXT: hasOpaqueSPAdjustment: false
 # CHECK-NEXT: hasVAStart: false
 # CHECK-NEXT: hasMustTailInVarArgFunc: false
diff --git a/llvm/test/CodeGen/X86/GlobalISel/irtranslator-call.ll b/llvm/test/CodeGen/X86/GlobalISel/irtranslator-call.ll
index c1bf4441766..bc394f6e156 100644
--- a/llvm/test/CodeGen/X86/GlobalISel/irtranslator-call.ll
+++ b/llvm/test/CodeGen/X86/GlobalISel/irtranslator-call.ll
@@ -20,7 +20,6 @@ define void @test_void_return() {
 ; CHECK-NEXT:   maxAlignment:    0
 ; CHECK-NEXT:   adjustsStack:    false
 ; CHECK-NEXT:   hasCalls:        false
-; CHECK-NEXT:   maxCallFrameSize: 0
 ; CHECK-NEXT:   hasOpaqueSPAdjustment: false
 ; CHECK-NEXT:   hasVAStart:      false
 ; CHECK-NEXT:   hasMustTailInVarArgFunc: false