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From: "danglin at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/44632] [4.4/4.5/4.6 regression] wrong code for complex division
Date: Sat, 07 Aug 2010 19:52:00 -0000	[thread overview]
Message-ID: <20100807195211.1851.qmail@sourceware.org> (raw)
In-Reply-To: <bug-44632-11764@http.gcc.gnu.org/bugzilla/>



------- Comment #2 from danglin at gcc dot gnu dot org  2010-08-07 19:52 -------
With slightly modified test,

#include <complex>
#include <iostream>

void g(std::complex<double> x)
{
     std::cout << x << std::endl;
}

void f(std::complex<double> x)
{
     g (x);
     x = 1.0 / x;
     g (x);
}

int main()
{
     f(2.0);
}

it appears RTL is wrong at expansion:

;; x.1 = std::operator/<double> (&D.24646, &x.1); [return slot optimization]

(insn 18 17 19 (set (reg:SI 102)
        (plus:SI (reg/f:SI 90 virtual-stack-vars)
            (const_int 8 [0x8]))) test.cxx:12 -1
     (nil))
(insn 19 18 20 (set (reg:SI 103)
        (plus:SI (reg/f:SI 90 virtual-stack-vars)
            (const_int 8 [0x8]))) test.cxx:12 -1
     (nil))

(insn 20 19 21 (set (reg:SI 28 %r28)
        (reg:SI 103)) test.cxx:12 -1
     (nil))

(insn 21 20 22 (set (reg:SI 26 %r26)
        (reg/f:SI 90 virtual-stack-vars)) test.cxx:12 -1
     (nil))

(insn 22 21 23 (set (reg:SI 25 %r25)
        (reg:SI 102)) test.cxx:12 -1
     (nil))

(call_insn 23 22 0 (parallel [
            (call (mem:SI (symbol_ref/v/i:SI
("@_ZStdvIdESt7complexIT_ERKS1_RKS2_") [flags 0x1]  <function_decl 0x40f5d600
operator/>) [0 S4 A32])
                (const_int 16 [0x10]))
            (clobber (reg:SI 1 %r1))
            (clobber (reg:SI 2 %r2))
            (use (const_int 0 [0]))
        ]) test.cxx:12 -1
     (nil)
    (expr_list:REG_DEP_TRUE (use (reg:SI 25 %r25))
        (expr_list:REG_DEP_TRUE (use (reg:SI 26 %r26))
            (expr_list:REG_DEP_TRUE (use (reg:SI 28 %r28))
                (nil)))))


-- 

danglin at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|target                      |tree-optimization


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44632


  parent reply	other threads:[~2010-08-07 19:52 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-06-22 13:58 [Bug target/44632] New: " doko at ubuntu dot com
2010-06-22 14:30 ` [Bug target/44632] " rguenth at gcc dot gnu dot org
2010-06-24 22:03 ` rguenth at gcc dot gnu dot org
2010-08-07 19:14 ` danglin at gcc dot gnu dot org
2010-08-07 19:33 ` danglin at gcc dot gnu dot org
2010-08-07 19:52 ` danglin at gcc dot gnu dot org [this message]
2010-08-07 19:58 ` [Bug tree-optimization/44632] " danglin at gcc dot gnu dot org
2010-08-07 19:59 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-07 20:37 ` rguenth at gcc dot gnu dot org
2010-08-07 20:39 ` rguenth at gcc dot gnu dot org
2010-08-07 20:40 ` rguenth at gcc dot gnu dot org
2010-08-07 20:57 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-07 21:00 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-07 21:04 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-07 21:16 ` rguenth at gcc dot gnu dot org
2010-08-07 21:36 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-09 11:35 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-09 11:37 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-09 11:44 ` dave at hiauly1 dot hia dot nrc dot ca
2010-08-09 11:51 ` rguenther at suse dot de
2010-08-09 13:18 ` rguenth at gcc dot gnu dot org
2010-08-09 13:31 ` [Bug tree-optimization/44632] [4.4/4.5 " rguenth at gcc dot gnu dot org
2010-08-16 20:18 ` danglin at gcc dot gnu dot org
2010-08-16 20:25 ` danglin at gcc dot gnu dot org
2010-08-16 20:27 ` danglin at gcc dot gnu dot org

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