Fix trap instruction on pp64

[• espindola]

Summary

The test was passing on a big endian host, but just because od with x4 was compensating for it.

[ruiu]

LGTM

ELF/Arch/PPC64.cpp

97–98

Something like this would be a bit simpler:

TrapInstr = (Config->IsLE == sys::IsLittleEndianHost) ? ...;

[• espindola]

r330386

ELF/Arch/PPC64.cpp

PPC64::PPC64() {
   //   It is normally desirable to put segments with different characteristics
   //   in separate 256 Mbyte portions of the address space, to give the
   //   operating system full paging flexibility in the 64-bit address space.
   //
   // And because the lowest non-zero 256M boundary is 0x10000000, PPC64 linkers
   // use 0x10000000 as the starting address.
   DefaultImageBase = 0x10000000;
 
-  TrapInstr = 0x7fe00008;
+  bool IsBE = Config->EKind != ELF64LEKind;
+  TrapInstr = IsBE == sys::IsBigEndianHost ? 0x7fe00008 : 0x0800e07f;
 }
 
 static uint32_t getEFlags(InputFile *File) {
   // Get the e_flag from the input file and if it is unspecified, then set it to
   // the e_flag appropriate for the ABI.
 
   // We are currently handling both ELF64LE and ELF64BE but eventually will
   // remove BE support once v2 ABI support is complete.

test/ELF/fill-trap-ppc.s

 # REQUIRES: ppc
 
 # RUN: llvm-mc -filetype=obj -triple=powerpc64le-linux %s -o %t.o
 # RUN: ld.lld %t.o -o %t.ppc64le
 # RUN: llvm-readobj -program-headers %t.ppc64le | FileCheck %s
-# RUN: od -Ax -t x4 -N16 -j0x10ff0 %t.ppc64le | FileCheck %s -check-prefix=FILL
+# RUN: od -Ax -t x1 -N16 -j0x10ff0 %t.ppc64le | FileCheck %s -check-prefix=LE
 
 # RUN: llvm-mc -filetype=obj -triple=powerpc64-linux %s -o %t.o
 # RUN: ld.lld %t.o -o %t.ppc64
 # RUN: llvm-readobj -program-headers %t.ppc64 | FileCheck %s
-# RUN: od -Ax -t x4 -N16 -j0x10ff0 %t.ppc64 | FileCheck %s -check-prefix=FILL
+# RUN: od -Ax -t x1 -N16 -j0x10ff0 %t.ppc64 | FileCheck %s -check-prefix=BE
 
 # CHECK: ProgramHeader {
 # CHECK:   Type: PT_LOAD
 # CHECK:        Offset: 0x10000{{$}}
 # CHECK-NEXT:   VirtualAddress:
 # CHECK-NEXT:   PhysicalAddress:
 # CHECK-NEXT:   FileSize: 4096
 # CHECK-NEXT:   MemSize:
 # CHECK-NEXT:   Flags [
 # CHECK-NEXT:     PF_R
 # CHECK-NEXT:     PF_X
 # CHECK-NEXT:   ]
 
 ## Check that executable page is filled with traps at its end.
-# FILL: 010ff0 7fe00008 7fe00008 7fe00008 7fe00008
+# LE: 010ff0 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f
+# BE: 010ff0 7f e0 00 08 7f e0 00 08 7f e0 00 08 7f e0 00 08
 
 .globl _start
 _start:
   nop