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[debug] Fix pre_dec handling in vartrack

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When compiling test-case gcc.target/i386/vartrack-1.c with -O1 -g, register bx
is pushed in the prologue and popped in the epilogue:
...
(insn/f 26 3 27 2
  (set (mem:DI (pre_dec:DI (reg/f:DI 7 sp)) [0  S8 A8])
       (reg:DI 3 bx))
   "vartrack-1.c":10 61 {*pushdi2_rex64}
   (expr_list:REG_DEAD (reg:DI 3 bx) (nil)))
  ...
(insn/f 29 28 30 2
  (set (reg:DI 3 bx)
       (mem:DI (post_inc:DI (reg/f:DI 7 sp)) [0  S8 A8]))
   "vartrack-1.c":15 71 {*popdi1}
   (expr_list:REG_CFA_ADJUST_CFA
     (set (reg/f:DI 7 sp)
          (plus:DI (reg/f:DI 7 sp)
                   (const_int 8 [0x8]))) (nil)))
...

However, when we adjust those insns in vartrack to eliminate the pre_dec and
post_inc, the frame location for the push is at argp - 24, while the one for the
pop is at argp - 16:
...
(insn/f 26 3 27 2
  (parallel [
    (set (mem:DI (plus:DI (reg/f:DI 16 argp)
                          (const_int -24 [0xffffffffffffffe8])) [0  S8 A8])
         (reg:DI 3 bx))
    (set (reg/f:DI 7 sp)
         (plus:DI (reg/f:DI 16 argp)
                  (const_int -24 [0xffffffffffffffe8])))
  ])
  "vartrack-1.c":10 61 {*pushdi2_rex64}
  (expr_list:REG_DEAD (reg:DI 3 bx) (nil)))
  ...
(insn/f 29 28 30 2
  (parallel [
    (set (reg:DI 3 bx)
         (mem:DI (plus:DI (reg/f:DI 16 argp)
                          (const_int -16 [0xfffffffffffffff0])) [0  S8 A8]))
    (set (reg/f:DI 7 sp)
         (plus:DI (reg/f:DI 16 argp)
                  (const_int -8 [0xfffffffffffffff8])))
  ])
  "vartrack-1.c":15 71 {*popdi1}
  (expr_list:REG_CFA_ADJUST_CFA
    (set (reg/f:DI 7 sp)
         (plus:DI (reg/f:DI 7 sp)
                  (const_int 8 [0x8]))) (nil)))
...

This patch fixes that by moving the stack_adjust modification after
adjust_insn in vt_initialize.

Bootstrapped and reg-tested on x86_64.

2018-07-16  Tom de Vries  <tdevries@suse.de>

	PR debug/86455
	* var-tracking.c (vt_initialize): Fix pre_dec handling.

	* gcc.target/i386/vartrack-1.c: New test.

From-SVN: r262687
This commit is contained in:
Tom de Vries 2018-07-16 09:18:51 +00:00 • committed by Tom de Vries
parent 1d896f48fa
commit 8c0e07e384
4 changed files with 42 additions and 1 deletions
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5
gcc/ChangeLog
View file

@ -1,3 +1,8 @@
2018-07-16 Tom de Vries <tdevries@suse.de>
PR debug/86455
* var-tracking.c (vt_initialize): Fix pre_dec handling.
2018-07-16 Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>
* config/aarch64/atomics.md (aarch64_store_execlusive<mode>): Add

5
gcc/testsuite/ChangeLog
View file

@ -1,3 +1,8 @@
2018-07-16 Tom de Vries <tdevries@suse.de>
PR debug/86455
* gcc.target/i386/vartrack-1.c: New test.
2018-07-16 Eric Botcazou <ebotcazou@adacore.com>
* gnat.dg/opt73.adb: New test.

28
gcc/testsuite/gcc.target/i386/vartrack-1.c Normal file
View file

@ -0,0 +1,28 @@
/* { dg-require-effective-target lp64 } */
/* { dg-options "-O1 -g -fdump-rtl-vartrack-details-slim" } */
static volatile int vv = 1;
extern long foo (long x);
int
main ()
{
long x = vv;
foo (x);
foo (x + 1);
return 0;
}
/* Before adjust_insn:
26: [--sp:DI]=bx:DI
29: bx:DI=[sp:DI++]
after adjust_insn:
26: {[argp:DI-0x10]=bx:DI;sp:DI=argp:DI-0x10;}
29: {bx:DI=[argp:DI-0x10];sp:DI=argp:DI-0x8;} */
/* { dg-final { scan-rtl-dump-times {[0-9][0-9]*: \{\[argp:DI-0x10\]=bx:DI;sp:DI=argp:DI-0x10;\}} 1 "vartrack" } } */
/* { dg-final { scan-rtl-dump-times {[0-9][0-9]*: \{bx:DI=\[argp:DI-0x10\];sp:DI=argp:DI-0x8;\}} 1 "vartrack" } } */

5
gcc/var-tracking.c
View file

@ -10209,12 +10209,15 @@ vt_initialize (void)
log_op_type (PATTERN (insn), bb, insn,
MO_ADJUST, dump_file);
VTI (bb)->mos.safe_push (mo);
VTI (bb)->out.stack_adjust += pre;
}
}
cselib_hook_called = false;
adjust_insn (bb, insn);
if (!frame_pointer_needed && pre)
VTI (bb)->out.stack_adjust += pre;
if (DEBUG_MARKER_INSN_P (insn))
{
reemit_marker_as_note (insn);