Refactor data-in-code annotations.

Use a dedicated MachO load command to annotate data-in-code regions.
This is the same format the linker produces for final executable images,
allowing consistency of representation and use of introspection tools
for both object and executable files.

Data-in-code regions are annotated via ".data_region"/".end_data_region"
directive pairs, with an optional region type.

data_region_directive := ".data_region" { region_type }
region_type := "jt8" | "jt16" | "jt32" | "jta32"
end_data_region_directive := ".end_data_region"

The previous handling of ARM-style "$d.*" labels was broken and has
been removed. Specifically, it didn't handle ARM vs. Thumb mode when
marking the end of the section.

rdar://11459456

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157062 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 51 deletions

diff --git a/include/llvm/MC/MCStreamer.h b/include/llvm/MC/MCStreamer.h
index 25956008e0..44c5fefaa1 100644
--- a/include/llvm/MC/MCStreamer.h
+++ b/include/llvm/MC/MCStreamer.h
@@ -69,22 +69,7 @@ namespace llvm {
     SmallVector<std::pair<const MCSection *,
                 const MCSection *>, 4> SectionStack;
 
-    unsigned UniqueCodeBeginSuffix;
-    unsigned UniqueDataBeginSuffix;
-
   protected:
-    /// Indicator of whether the previous data-or-code indicator was for
-    /// code or not.  Used to determine when we need to emit a new indicator.
-    enum DataType {
-      Data,
-      Code,
-      JumpTable8,
-      JumpTable16,
-      JumpTable32
-    };
-    DataType RegionIndicator;
-
-
     MCStreamer(MCContext &Ctx);
 
     const MCExpr *BuildSymbolDiff(MCContext &Context, const MCSymbol *A,
@@ -241,47 +226,15 @@ namespace llvm {
     /// used in an assignment.
     virtual void EmitLabel(MCSymbol *Symbol);
 
-    /// EmitDataRegion - Emit a label that marks the beginning of a data
-    /// region.
-    /// On ELF targets, this corresponds to an assembler statement such as:
-    ///   $d.1:
-    virtual void EmitDataRegion();
-
-    /// EmitJumpTable8Region - Emit a label that marks the beginning of a
-    /// jump table composed of 8-bit offsets.
-    /// On ELF targets, this corresponds to an assembler statement such as:
-    ///   $d.1:
-    virtual void EmitJumpTable8Region();
-
-    /// EmitJumpTable16Region - Emit a label that marks the beginning of a
-    /// jump table composed of 16-bit offsets.
-    /// On ELF targets, this corresponds to an assembler statement such as:
-    ///   $d.1:
-    virtual void EmitJumpTable16Region();
-
-    /// EmitJumpTable32Region - Emit a label that marks the beginning of a
-    /// jump table composed of 32-bit offsets.
-    /// On ELF targets, this corresponds to an assembler statement such as:
-    ///   $d.1:
-    virtual void EmitJumpTable32Region();
-
-    /// EmitCodeRegion - Emit a label that marks the beginning of a code
-    /// region.
-    /// On ELF targets, this corresponds to an assembler statement such as:
-    ///   $a.1:
-    virtual void EmitCodeRegion();
-
-    /// ForceCodeRegion - Forcibly sets the current region mode to code.  Used
-    /// at function entry points.
-    void ForceCodeRegion() { RegionIndicator = Code; }
-
-
     virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
                                      MCSymbol *EHSymbol);
 
-    /// EmitAssemblerFlag - Note in the output the specified @p Flag
+    /// EmitAssemblerFlag - Note in the output the specified @p Flag.
     virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) = 0;
 
+    /// EmitDataRegion - Note in the output the specified region @p Kind.
+    virtual void EmitDataRegion(MCDataRegionType Kind) {}
+
     /// EmitThumbFunc - Note in the output that the specified @p Func is
     /// a Thumb mode function (ARM target only).
     virtual void EmitThumbFunc(MCSymbol *Func) = 0;