[Bug target/52206] New: Strange %P in stack_tls_protect_set_<mode> and movabs patterns

["hjl.tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52206

             Bug #: 52206
           Summary: Strange %P in stack_tls_protect_set_<mode> and movabs
                    patterns
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hjl.tools@gmail.com
                CC: ubizjak@gmail.com
            Target: x86_64


i386.md has

(define_insn "stack_tls_protect_set_<mode>"
  [(set (match_operand:P 0 "memory_operand" "=m") 
        (unspec:P [(match_operand:P 1 "const_int_operand" "i")] 
                  UNSPEC_SP_TLS_SET))
   (set (match_scratch:P 2 "=&r") (const_int 0))
   (clobber (reg:CC FLAGS_REG))]
  ""
  "mov{<imodesuffix>}\t{%@:%P1, %2|%2, <iptrsize> PTR
%@:%P1}\;mov{<imodesuffix>}\t{%2, %0|%0, %2}\;xor{l}\t%k2, %k2"
  [(set_attr "type" "multi")])

Operand 1 is always a constant generated by

 operands[1] = GEN_INT (TARGET_THREAD_SSP_OFFSET);
  insn = (TARGET_LP64
          ? gen_stack_tls_protect_set_di
          : gen_stack_tls_protect_set_si);

(define_insn "*movabs<mode>_1"
  [(set (mem:SWI1248x (match_operand:DI 0 "x86_64_movabs_operand" "i,r"))
        (match_operand:SWI1248x 1 "nonmemory_operand" "a,er"))]
  "TARGET_64BIT && ix86_check_movabs (insn, 0)"
  "@
   movabs{<imodesuffix>}\t{%1, %P0|%P0, %1}
   mov{<imodesuffix>}\t{%1, %a0|%a0, %1}"
  [(set_attr "type" "imov")
   (set_attr "modrm" "0,*")
   (set_attr "length_address" "8,0")
   (set_attr "length_immediate" "0,*")
   (set_attr "memory" "store")
   (set_attr "mode" "<MODE>")])

(define_insn "*movabs<mode>_2"
  [(set (match_operand:SWI1248x 0 "register_operand" "=a,r")
        (mem:SWI1248x (match_operand:DI 1 "x86_64_movabs_operand" "i,r")))]
  "TARGET_64BIT && ix86_check_movabs (insn, 1)"
  "@
   movabs{<imodesuffix>}\t{%P1, %0|%0, %P1}
   mov{<imodesuffix>}\t{%a1, %0|%0, %a1}"
  [(set_attr "type" "imov")
   (set_attr "modrm" "0,*")
   (set_attr "length_address" "8,0")
   (set_attr "length_immediate" "0")
   (set_attr "memory" "load")
   (set_attr "mode" "<MODE>")])

The P code is only used on symbol for

P -- if PIC, print an @PLT suffix.

Why do we need it on immediate operand?