This is a resubmittal. For some reason it broke the bots yesterday

but I cannot reproduce the problem and have scrubed my sources and
even tested with llvm-lit -v --vg.
Support for Mips register information sections.

Mips ELF object files have a section that is dedicated
to register use info. Some of this information such as
the assumed Global Pointer value is used by the linker
in relocation resolution.

The register info file is .reginfo in o32 and .MIPS.options
in 64 and n32 abi files.

This patch contains the changes needed to create the sections,
but leaves the actual register accounting for a future patch.


Contributer: Jack Carter
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172847 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 80 insertions, 0 deletions

diff --git a/lib/Target/Mips/MCTargetDesc/MipsReginfo.cpp b/lib/Target/Mips/MCTargetDesc/MipsReginfo.cpp
new file mode 100644
index 0000000000..1dc9bcb36a
--- /dev/null
+++ b/lib/Target/Mips/MCTargetDesc/MipsReginfo.cpp
@@ -0,0 +1,80 @@
+//===-- MipsReginfo.cpp - Registerinfo handling  --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+// .reginfo
+//    Elf32_Word ri_gprmask
+//    Elf32_Word ri_cprmask[4]
+//    Elf32_Word ri_gp_value
+//
+// .MIPS.options - N64
+//    Elf64_Byte    kind (ODK_REGINFO)
+//    Elf64_Byte    size (40 bytes)
+//    Elf64_Section section (0)
+//    Elf64_Word    info (unused)
+//    Elf64_Word    ri_gprmask ()
+//    Elf64_Word    ri_pad ()
+//    Elf64_Word[4] ri_cprmask ()
+//    Elf64_Addr    ri_gp_value ()
+//
+// .MIPS.options - N32
+//    Elf32_Byte    kind (ODK_REGINFO)
+//    Elf32_Byte    size (36 bytes)
+//    Elf32_Section section (0)
+//    Elf32_Word    info (unused)
+//    Elf32_Word    ri_gprmask ()
+//    Elf32_Word    ri_pad ()
+//    Elf32_Word[4] ri_cprmask ()
+//    Elf32_Addr    ri_gp_value ()
+//
+//===----------------------------------------------------------------------===//
+#include "MCTargetDesc/MipsReginfo.h"
+#include "MipsSubtarget.h"
+#include "MipsTargetObjectFile.h"
+#include "llvm/MC/MCStreamer.h"
+
+using namespace llvm;
+
+// Integrated assembler version
+void
+MipsReginfo::emitMipsReginfoSectionCG(MCStreamer &OS,
+    const TargetLoweringObjectFile &TLOF,
+    const MipsSubtarget &MST) const
+{
+
+  if (OS.hasRawTextSupport())
+    return;
+
+  const MipsTargetObjectFile &TLOFELF =
+      static_cast<const MipsTargetObjectFile &>(TLOF);
+  OS.SwitchSection(TLOFELF.getReginfoSection());
+
+  // .reginfo
+  if (MST.isABI_O32()) {
+    OS.EmitIntValue(0, 4); // ri_gprmask
+    OS.EmitIntValue(0, 4); // ri_cpr[0]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[1]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[2]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[3]mask
+    OS.EmitIntValue(0, 4); // ri_gp_value
+  }
+  // .MIPS.options
+  else if (MST.isABI_N64()) {
+    OS.EmitIntValue(1, 1); // kind
+    OS.EmitIntValue(40, 1); // size
+    OS.EmitIntValue(0, 2); // section
+    OS.EmitIntValue(0, 4); // info
+    OS.EmitIntValue(0, 4); // ri_gprmask
+    OS.EmitIntValue(0, 4); // pad
+    OS.EmitIntValue(0, 4); // ri_cpr[0]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[1]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[2]mask
+    OS.EmitIntValue(0, 4); // ri_cpr[3]mask
+    OS.EmitIntValue(0, 8); // ri_gp_value
+  }
+  else llvm_unreachable("Unsupported abi for reginfo");
+}
+