On 05/15/2013 04:50 AM, Ramana Radhakrishnan wrote:
> /* Cannot tail-call to long calls, since these are out of range of
> a branch instruction. */
> - if (arm_is_long_call_p (decl))
> + if (decl && arm_is_long_call_p (decl))
> return false;
You can tail call long calls via indirection now. I.e. load the address first.
> (define_insn "*sibcall_insn"
> - [(call (mem:SI (match_operand:SI 0 "" "X"))
> + [(call (mem:SI (match_operand:SI 0 "call_insn_operand" "Cs,Ss"))
FWIW, "i" or "s" would work just as well, given you've already constrained by
call_insn_operand; Ss isn't really needed.
> + if (arm_arch5 || arm_arch4t)
> + return \" bx\\t%0\\t%@ indirect register sibling call\";
Missing %?.
> + if (arm_arch5 || arm_arch4t)
> + return \"bx\\t%1\";
Likewise.
> diff --git a/gcc/testsuite/gcc.target/arm/pr40887.c
> b/gcc/testsuite/gcc.target/arm/pr40887.c
> index 0b5e873..5cabe3a 100644
> --- a/gcc/testsuite/gcc.target/arm/pr40887.c
> +++ b/gcc/testsuite/gcc.target/arm/pr40887.c
> @@ -2,9 +2,9 @@
> /* { dg-options "-O2 -march=armv5te" } */
> /* { dg-final { scan-assembler "blx" } } */
>
> -int (*indirect_func)();
> +int (*indirect_func)(int x);
>
> int indirect_call()
> {
> - return indirect_func();
> + return indirect_func(20) + indirect_func (40);
> }
>
You've made this test case 100% useless. Of course there will always be a blx
insn, since you've two calls there, and one of them will never be tail called.
It should have been either removed or become your new test case.
r~
