[Bug middle-end/71304] missing strlen optimizations after string truncation by assigning NUL

[lesliezhai at llvm dot org.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71304

Leslie Zhai <lesliezhai at llvm dot org.cn> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lesliezhai at llvm dot org.cn

--- Comment #4 from Leslie Zhai <lesliezhai at llvm dot org.cn> ---
(In reply to Martin Sebor from comment #3)
> Not working on the patch anymore.

GCC 8.x works:
$ /opt/mips-gnu-git/bin/mips64-linux-gnu-gcc -O2 -S -Wall -Wextra
-fdump-tree-optimized=/dev/stdout -o/dev/stdout t.c           
        .file   1 "t.c"
        .section .mdebug.abi64
        .previous
        .nan    legacy
        .module fp=64
        .module oddspreg
        .abicalls
        .text

;; Function f (f, funcdef_no=0, decl_uid=1582, cgraph_uid=0, symbol_order=0)

f ()
{
  <bb 2> [local count: 1073741825]:
  return 1;

}


        .align  2
        .align  3
        .globl  f
        .set    nomips16
        .set    nomicromips
        .ent    f
        .type   f, @function
f:
        .frame  $sp,0,$31               # vars= 0, regs= 0/0, args= 0, gp= 0
        .mask   0x00000000,0
        .fmask  0x00000000,0
        .set    noreorder
        .set    nomacro
        jr      $31
        li      $2,1                    # 0x1

        .set    macro
        .set    reorder
        .end    f
        .size   f, .-f

;; Function g (g, funcdef_no=1, decl_uid=1586, cgraph_uid=1, symbol_order=1)

g ()
{
  <bb 2> [local count: 1073741825]:
  return 1;

}


        .align  2
        .align  3
        .globl  g
        .set    nomips16
        .set    nomicromips
        .ent    g
        .type   g, @function
g:
        .frame  $sp,0,$31               # vars= 0, regs= 0/0, args= 0, gp= 0
        .mask   0x00000000,0
        .fmask  0x00000000,0
        .set    noreorder
        .set    nomacro
        jr      $31
        li      $2,1                    # 0x1

        .set    macro
        .set    reorder
        .end    g
        .size   g, .-g
        .ident  "GCC: (GNU) 8.0.1 20180123 (experimental)"


Could you tell me which commit fix the issue please? thanks a lot!

Regards,
Leslie Zhai