From: Dibyendu Majumdar <mobile@majumdar.org.uk>
To: David Malcolm <dmalcolm@redhat.com>
Cc: jit@gcc.gnu.org
Subject: Re: Filed PR jit/66812 for the code generation issue
Date: Thu, 01 Jan 2015 00:00:00 -0000 [thread overview]
Message-ID: <CACXZuxcXRryS_w_kA0y=V8sNzy6=JGMON-ciO6Ys21axwJFmMw@mail.gmail.com> (raw)
In-Reply-To: <CACXZuxc-AmXDbAmu=ZDQrxf_rOtXUS-gB1_p_vTRB_kPEH9WmA@mail.gmail.com>
Here is what I think the flow is.
part 1
--------
1 [2] LOADNIL 0 0
entry:
cl = (struct ravi_LClosure *)L->ci->func->value_.gc;
(void)raviV_op_loadnil (L->ci, (int)0, (int)0);
This sets register 0 (local variable IX) to NIL
2 [3] LOADK 1 -1 ; 10
(&L->ci->u.l.base[(int)1])->value_.i = (&cl->p->k[(int)0])->value_.i;
(&L->ci->u.l.base[(int)1])->tt_ = (&cl->p->k[(int)0])->tt_;
This sets the register at 1 (temporary) to 10.
3 [3] TEST 1 1
4 [3] JMP 0 0 ; to 5
The above two bytecodes go together. This says that if register 1 is
true then skip the JMP else JMP.
So we get:
comparison_0_5 = (&L->ci->u.l.base[(int)1])->tt_ == (int)0;
comparison_0_6 = (&L->ci->u.l.base[(int)1])->tt_ == (int)1;
comparison_0_7 = (&L->ci->u.l.base[(int)1])->value_.b == (int)0;
isfalse_0_4 = comparison_0_5 || comparison_0_6 && comparison_0_7;
if (!(isfalse_0_4)) goto OP_TEST_do_jmp_2_8; else goto OP_TEST_do_skip_2_9;
The test is checking that register 1 is true (which it is as it has
the constant 10) - then goto skip_2_9.
next prev parent reply other threads:[~2015-07-08 20:22 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-01 0:00 A possible " Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Filed PR jit/66811: jit jumps aren't compilable as C (Re: A possible code generation issue) David Malcolm
2015-01-01 0:00 ` Filed PR jit/66811: jit dumps " David Malcolm
2015-01-01 0:00 ` A possible code generation issue Dibyendu Majumdar
2015-01-01 0:00 ` PR jit/66783 (Re: A possible code generation issue) David Malcolm
2015-01-01 0:00 ` [PATCH, committed] PR jit/66783: prevent use of opaque structs David Malcolm
2015-01-01 0:00 ` Filed PR jit/66812 for the code generation issue David Malcolm
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar [this message]
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` [PATCH] PR jit/66812: Candidate fix for for the code generation issue, v1 David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` David Malcolm
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
2015-01-01 0:00 ` Filed PR jit/66812 for the code generation issue Dibyendu Majumdar
2015-01-01 0:00 ` Dibyendu Majumdar
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