[Thumb] Set correct initial mapping symbol for big-endian thumb

[olista01]

Summary

The initial mapping symbol state is set from the triple, but we only checked for the little-endian thumb triple, so could end up with an ARM mapping symbol for big-endian thumb.

[rengolin]

Ouch! Thanks for the fix. LGTM.

--renato

llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp

static MCAsmInfo *createARMMCAsmInfo(const MCRegisterInfo &MRI,
 
   return MAI;
 }
 
 static MCStreamer *createELFStreamer(const Triple &T, MCContext &Ctx,
                                      MCAsmBackend &MAB, raw_pwrite_stream &OS,
                                      MCCodeEmitter *Emitter, bool RelaxAll) {
   return createARMELFStreamer(Ctx, MAB, OS, Emitter, false,
-                              T.getArch() == Triple::thumb);
+                              (T.getArch() == Triple::thumb ||
+                               T.getArch() == Triple::thumbeb));
 }
 
 static MCStreamer *createARMMachOStreamer(MCContext &Ctx, MCAsmBackend &MAB,
                                           raw_pwrite_stream &OS,
                                           MCCodeEmitter *Emitter, bool RelaxAll,
                                           bool DWARFMustBeAtTheEnd) {
   return createMachOStreamer(Ctx, MAB, OS, Emitter, false, DWARFMustBeAtTheEnd);
 }

llvm/trunk/test/MC/ARM/mapping-initial.s

+@ RUN: llvm-mc -triple=armv7a-none-eabi     -filetype=obj < %s | llvm-objdump -t - | FileCheck %s --check-prefix=ARM
+@ RUN: llvm-mc -triple=armebv7a-none-eabi   -filetype=obj < %s | llvm-objdump -t - | FileCheck %s --check-prefix=ARM
+@ RUN: llvm-mc -triple=thumbv7a-none-eabi   -filetype=obj < %s | llvm-objdump -t - | FileCheck %s --check-prefix=THUMB
+@ RUN: llvm-mc -triple=thumbebv7a-none-eabi -filetype=obj < %s | llvm-objdump -t - | FileCheck %s --check-prefix=THUMB
+
+  add r0, r0, r0
+
+@ ARM:      00000000         .text  00000000 $a
+@ THUMB:    00000000         .text  00000000 $t