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From: "unlvsur at live dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/114215] GCC makes wrong decision for inline with -Os or -Oz to deal with trivial functions
Date: Sun, 03 Mar 2024 03:30:03 +0000	[thread overview]
Message-ID: <bug-114215-4-xum1yNowhl@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114215-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114215

--- Comment #4 from cqwrteur <unlvsur at live dot com> ---
void test_demovector(checkedvector& vec, __SIZE_TYPE__ x) noexcept
{
  for(__SIZE_TYPE__ i = 0; i < x; i++)
    vec[i]=5;
}

void test_demovector_forceinline(checkedvector& vec, __SIZE_TYPE__ x) noexcept
{
  for(__SIZE_TYPE__ i = 0; i < x; i++)
    vec.index_forceinline(i)=5;
}

still more instructions for the first one even with a loop.

test_demovector(checkedvector&, unsigned long):
        pushq   %r12
        movq    %rdi, %r12
        pushq   %rbp
        movq    %rsi, %rbp
        pushq   %rbx
        xorl    %ebx, %ebx
.L10:
        cmpq    %rbp, %rbx
        je      .L13
        movq    %rbx, %rsi
        movq    %r12, %rdi
        incq    %rbx
        call    checkedvector::operator[](unsigned long)
        movq    $5, (%rax)
        jmp     .L10
.L13:
        popq    %rbx
        popq    %rbp
        popq    %r12
        ret



test_demovector_forceinline(checkedvector&, unsigned long):
        xorl    %eax, %eax
.L15:
        cmpq    %rsi, %rax
        je      .L18
        movq    (%rdi), %rcx
        movq    8(%rdi), %rdx
        subq    %rcx, %rdx
        sarq    $3, %rdx
        cmpq    %rdx, %rax
        jb      .L16
        ud2
.L16:
        movq    $5, (%rcx,%rax,8)
        incq    %rax
        jmp     .L15
.L18:
        ret

  parent reply	other threads:[~2024-03-03  3:30 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-03  2:53 [Bug rtl-optimization/114215] New: " unlvsur at live dot com
2024-03-03  3:06 ` [Bug ipa/114215] " pinskia at gcc dot gnu.org
2024-03-03  3:18 ` pinskia at gcc dot gnu.org
2024-03-03  3:27 ` unlvsur at live dot com
2024-03-03  3:30 ` unlvsur at live dot com [this message]
2024-03-03  3:36 ` pinskia at gcc dot gnu.org
2024-03-03  3:44 ` [Bug ipa/114215] -Os or -Oz inlining seems wrong for vague linkage functions unlvsur at live dot com
2024-03-03  3:45 ` unlvsur at live dot com
2024-03-06  2:23 ` unlvsur at live dot com

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