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, 8 insertions, 20 deletions

diff --git a/include/llvm/MC/MCAsmInfo.h b/include/llvm/MC/MCAsmInfo.h
index 16964c3c9d..ae0dad2fd1 100644
--- a/include/llvm/MC/MCAsmInfo.h
+++ b/include/llvm/MC/MCAsmInfo.h
@@ -147,6 +147,11 @@ namespace llvm {
     // FIXME: Make this a more general encoding setting?
     bool AllowUTF8;
 
+    /// UseDataRegionDirectives - This is true if data region markers should
+    /// be printed as ".data_region/.end_data_region" directives. If false,
+    /// use "$d/$a" labels instead.
+    bool UseDataRegionDirectives;
+
     //===--- Data Emission Directives -------------------------------------===//
 
     /// ZeroDirective - this should be set to the directive used to get some
@@ -172,18 +177,6 @@ namespace llvm {
     const char *Data32bitsDirective;         // Defaults to "\t.long\t"
     const char *Data64bitsDirective;         // Defaults to "\t.quad\t"
 
-    /// [Data|Code]Begin - These magic labels are used to marked a region as
-    /// data or code, and are used to provide additional information for
-    /// correct disassembly on targets that like to mix data and code within
-    /// a segment.  These labels will be implicitly suffixed by the streamer
-    /// to give them unique names.
-    const char *DataBegin;                   // Defaults to "$d."
-    const char *CodeBegin;                   // Defaults to "$a."
-    const char *JT8Begin;                    // Defaults to "$a."
-    const char *JT16Begin;                   // Defaults to "$a."
-    const char *JT32Begin;                   // Defaults to "$a."
-    bool SupportsDataRegions;
-
     /// GPRel64Directive - if non-null, a directive that is used to emit a word
     /// which should be relocated as a 64-bit GP-relative offset, e.g. .gpdword
     /// on Mips.
@@ -384,14 +377,6 @@ namespace llvm {
     const char *getGPRel64Directive() const { return GPRel64Directive; }
     const char *getGPRel32Directive() const { return GPRel32Directive; }
 
-    /// [Code|Data]Begin label name accessors.
-    const char *getCodeBeginLabelName() const { return CodeBegin; }
-    const char *getDataBeginLabelName() const { return DataBegin; }
-    const char *getJumpTable8BeginLabelName() const { return JT8Begin; }
-    const char *getJumpTable16BeginLabelName() const { return JT16Begin; }
-    const char *getJumpTable32BeginLabelName() const { return JT32Begin; }
-    bool getSupportsDataRegions() const { return SupportsDataRegions; }
-
     /// getNonexecutableStackSection - Targets can implement this method to
     /// specify a section to switch to if the translation unit doesn't have any
     /// trampolines that require an executable stack.
@@ -488,6 +473,9 @@ namespace llvm {
     bool doesAllowUTF8() const {
       return AllowUTF8;
     }
+    bool doesSupportDataRegionDirectives() const {
+      return UseDataRegionDirectives;
+    }
     const char *getZeroDirective() const {
       return ZeroDirective;
     }