[Bug rtl-optimization/82803] Wildly excessive calls to __tls_get_addr with optimizations enabled.

[ebotcazou at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82803

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ebotcazou at gcc dot gnu.org

--- Comment #6 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> The main reason is __tls_get_addr emitted as a normal call on RTL (for each
> GIMPLE access to the variable), but unless I'm missing something RTL doesn't
> have a notion of pure/const calls, so RTL loop invariant motion and CSE
> cannot clean up the redundant calls.

/* 1 if RTX is a call to a const function.  Built from ECF_CONST and
   TREE_READONLY.  */
#define RTL_CONST_CALL_P(RTX)                                   \
  (RTL_FLAG_CHECK1 ("RTL_CONST_CALL_P", (RTX), CALL_INSN)->unchanging)

/* 1 if RTX is a call to a pure function.  Built from ECF_PURE and
   DECL_PURE_P.  */
#define RTL_PURE_CALL_P(RTX)                                    \
  (RTL_FLAG_CHECK1 ("RTL_PURE_CALL_P", (RTX), CALL_INSN)->return_val)

/* 1 if RTX is a call to a const or pure function.  */
#define RTL_CONST_OR_PURE_CALL_P(RTX) \
  (RTL_CONST_CALL_P (RTX) || RTL_PURE_CALL_P (RTX))

/* 1 if RTX is a call to a looping const or pure function.  Built from
   ECF_LOOPING_CONST_OR_PURE and DECL_LOOPING_CONST_OR_PURE_P.  */
#define RTL_LOOPING_CONST_OR_PURE_CALL_P(RTX)                           \
  (RTL_FLAG_CHECK1 ("CONST_OR_PURE_CALL_P", (RTX), CALL_INSN)->call)