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haileys/hello.cpp

Created October 12, 2011 08:06
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hello.cpp
#include <iostream>
using namespace std;
class HelloCppTest {
public:
static void testMain() {
cout << "Hello, C++er!" << endl;
}
};
int main() {
HelloCppTest::testMain();
}
Raw
hello.s
.mod_init_func
.align 3
.quad __GLOBAL__I_main
.section __TEXT,__textcoal_nt,coalesced,pure_instructions
.globl __ZSt3minImERKT_S2_S2_
.weak_definition __ZSt3minImERKT_S2_S2_
__ZSt3minImERKT_S2_S2_:
LFB1479:
pushq %rbp
LCFI0:
movq %rsp, %rbp
LCFI1:
movq %rdi, -8(%rbp)
movq %rsi, -16(%rbp)
movq -16(%rbp), %rax
movq (%rax), %rdx
movq -8(%rbp), %rax
movq (%rax), %rax
cmpq %rax, %rdx
jae L2
movq -16(%rbp), %rax
movq %rax, -24(%rbp)
jmp L4
L2:
movq -8(%rbp), %rax
movq %rax, -24(%rbp)
L4:
movq -24(%rbp), %rax
leave
ret
LFE1479:
.text
__ZStL17__verify_groupingPKcmRKSs:
LFB1407:
pushq %rbp
LCFI2:
movq %rsp, %rbp
LCFI3:
pushq %rbx
LCFI4:
subq $88, %rsp
LCFI5:
movq %rdi, -72(%rbp)
movq %rsi, -80(%rbp)
movq %rdx, -88(%rbp)
movq -88(%rbp), %rdi
call __ZNKSs4sizeEv
decq %rax
movq %rax, -32(%rbp)
movq -80(%rbp), %rax
decq %rax
movq %rax, -48(%rbp)
leaq -48(%rbp), %rsi
leaq -32(%rbp), %rdi
call __ZSt3minImERKT_S2_S2_
movq (%rax), %rax
movq %rax, -40(%rbp)
movq -32(%rbp), %rax
movq %rax, -56(%rbp)
movb $1, -17(%rbp)
movq $0, -64(%rbp)
jmp L7
L8:
movq -56(%rbp), %rsi
movq -88(%rbp), %rdi
call __ZNKSsixEm
movzbl (%rax), %edx
movq -64(%rbp), %rax
addq -72(%rbp), %rax
movzbl (%rax), %eax
cmpb %al, %dl
sete %al
movb %al, -17(%rbp)
decq -56(%rbp)
incq -64(%rbp)
L7:
movq -64(%rbp), %rax
cmpq -40(%rbp), %rax
jae L11
cmpb $0, -17(%rbp)
jne L8
jmp L11
L12:
movq -56(%rbp), %rsi
movq -88(%rbp), %rdi
call __ZNKSsixEm
movzbl (%rax), %edx
movq -40(%rbp), %rax
addq -72(%rbp), %rax
movzbl (%rax), %eax
cmpb %al, %dl
sete %al
movb %al, -17(%rbp)
decq -56(%rbp)
L11:
cmpq $0, -56(%rbp)
je L13
cmpb $0, -17(%rbp)
jne L12
L13:
movq -40(%rbp), %rax
addq -72(%rbp), %rax
movzbl (%rax), %eax
testb %al, %al
jle L15
movzbl -17(%rbp), %ebx
movq -88(%rbp), %rdi
movl $0, %esi
call __ZNKSsixEm
movzbl (%rax), %edx
movq -40(%rbp), %rax
addq -72(%rbp), %rax
movzbl (%rax), %eax
cmpb %al, %dl
setle %al
movzbl %al, %eax
andl %ebx, %eax
testl %eax, %eax
setne %al
movb %al, -17(%rbp)
L15:
movzbl -17(%rbp), %eax
addq $88, %rsp
popq %rbx
leave
ret
LFE1407:
.cstring
LC0:
.ascii "Hello, C++er!\0"
.section __TEXT,__textcoal_nt,coalesced,pure_instructions
.globl __ZN12HelloCppTest8testMainEv
.weak_definition __ZN12HelloCppTest8testMainEv
__ZN12HelloCppTest8testMainEv:
LFB1477:
pushq %rbp
LCFI6:
movq %rsp, %rbp
LCFI7:
leaq LC0(%rip), %rsi
movq __ZSt4cout@GOTPCREL(%rip), %rdi
call __ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc
movq %rax, %rdi
movq __ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_@GOTPCREL(%rip), %rsi
call __ZNSolsEPFRSoS_E
leave
ret
LFE1477:
.text
.globl _main
_main:
LFB1478:
pushq %rbp
LCFI8:
movq %rsp, %rbp
LCFI9:
call __ZN12HelloCppTest8testMainEv
movl $0, %eax
leave
ret
LFE1478:
.section __TEXT,__StaticInit,regular,pure_instructions
__Z41__static_initialization_and_destruction_0ii:
LFB1491:
pushq %rbp
LCFI10:
movq %rsp, %rbp
LCFI11:
subq $16, %rsp
LCFI12:
movl %edi, -4(%rbp)
movl %esi, -8(%rbp)
cmpl $1, -4(%rbp)
jne L26
cmpl $65535, -8(%rbp)
jne L26
leaq __ZStL8__ioinit(%rip), %rdi
call __ZNSt8ios_base4InitC1Ev
movq ___dso_handle@GOTPCREL(%rip), %rdx
movl $0, %esi
leaq ___tcf_0(%rip), %rdi
call ___cxa_atexit
L26:
leave
ret
LFE1491:
__GLOBAL__I_main:
LFB1493:
pushq %rbp
LCFI13:
movq %rsp, %rbp
LCFI14:
movl $65535, %esi
movl $1, %edi
call __Z41__static_initialization_and_destruction_0ii
leave
ret
LFE1493:
.text
___tcf_0:
LFB1492:
pushq %rbp
LCFI15:
movq %rsp, %rbp
LCFI16:
subq $16, %rsp
LCFI17:
movq %rdi, -8(%rbp)
leaq __ZStL8__ioinit(%rip), %rdi
call __ZNSt8ios_base4InitD1Ev
leave
ret
LFE1492:
.lcomm __ZStL8__ioinit,1,0
.section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
EH_frame1:
.set L$set$0,LECIE1-LSCIE1
.long L$set$0
LSCIE1:
.long 0x0
.byte 0x1
.ascii "zPR\0"
.byte 0x1
.byte 0x78
.byte 0x10
.byte 0x6
.byte 0x9b
.long ___gxx_personality_v0+4@GOTPCREL
.byte 0x10
.byte 0xc
.byte 0x7
.byte 0x8
.byte 0x90
.byte 0x1
.align 3
LECIE1:
.globl __ZSt3minImERKT_S2_S2_.eh
.weak_definition __ZSt3minImERKT_S2_S2_.eh
__ZSt3minImERKT_S2_S2_.eh:
LSFDE1:
.set L$set$1,LEFDE1-LASFDE1
.long L$set$1
LASFDE1:
.long LASFDE1-EH_frame1
.quad LFB1479-.
.set L$set$2,LFE1479-LFB1479
.quad L$set$2
.byte 0x0
.byte 0x4
.set L$set$3,LCFI0-LFB1479
.long L$set$3
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$4,LCFI1-LCFI0
.long L$set$4
.byte 0xd
.byte 0x6
.align 3
LEFDE1:
__ZStL17__verify_groupingPKcmRKSs.eh:
LSFDE3:
.set L$set$5,LEFDE3-LASFDE3
.long L$set$5
LASFDE3:
.long LASFDE3-EH_frame1
.quad LFB1407-.
.set L$set$6,LFE1407-LFB1407
.quad L$set$6
.byte 0x0
.byte 0x4
.set L$set$7,LCFI2-LFB1407
.long L$set$7
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$8,LCFI3-LCFI2
.long L$set$8
.byte 0xd
.byte 0x6
.byte 0x4
.set L$set$9,LCFI5-LCFI3
.long L$set$9
.byte 0x83
.byte 0x3
.align 3
LEFDE3:
.globl __ZN12HelloCppTest8testMainEv.eh
.weak_definition __ZN12HelloCppTest8testMainEv.eh
__ZN12HelloCppTest8testMainEv.eh:
LSFDE5:
.set L$set$10,LEFDE5-LASFDE5
.long L$set$10
LASFDE5:
.long LASFDE5-EH_frame1
.quad LFB1477-.
.set L$set$11,LFE1477-LFB1477
.quad L$set$11
.byte 0x0
.byte 0x4
.set L$set$12,LCFI6-LFB1477
.long L$set$12
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$13,LCFI7-LCFI6
.long L$set$13
.byte 0xd
.byte 0x6
.align 3
LEFDE5:
.globl _main.eh
_main.eh:
LSFDE7:
.set L$set$14,LEFDE7-LASFDE7
.long L$set$14
LASFDE7:
.long LASFDE7-EH_frame1
.quad LFB1478-.
.set L$set$15,LFE1478-LFB1478
.quad L$set$15
.byte 0x0
.byte 0x4
.set L$set$16,LCFI8-LFB1478
.long L$set$16
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$17,LCFI9-LCFI8
.long L$set$17
.byte 0xd
.byte 0x6
.align 3
LEFDE7:
__Z41__static_initialization_and_destruction_0ii.eh:
LSFDE9:
.set L$set$18,LEFDE9-LASFDE9
.long L$set$18
LASFDE9:
.long LASFDE9-EH_frame1
.quad LFB1491-.
.set L$set$19,LFE1491-LFB1491
.quad L$set$19
.byte 0x0
.byte 0x4
.set L$set$20,LCFI10-LFB1491
.long L$set$20
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$21,LCFI11-LCFI10
.long L$set$21
.byte 0xd
.byte 0x6
.align 3
LEFDE9:
__GLOBAL__I_main.eh:
LSFDE11:
.set L$set$22,LEFDE11-LASFDE11
.long L$set$22
LASFDE11:
.long LASFDE11-EH_frame1
.quad LFB1493-.
.set L$set$23,LFE1493-LFB1493
.quad L$set$23
.byte 0x0
.byte 0x4
.set L$set$24,LCFI13-LFB1493
.long L$set$24
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$25,LCFI14-LCFI13
.long L$set$25
.byte 0xd
.byte 0x6
.align 3
LEFDE11:
___tcf_0.eh:
LSFDE13:
.set L$set$26,LEFDE13-LASFDE13
.long L$set$26
LASFDE13:
.long LASFDE13-EH_frame1
.quad LFB1492-.
.set L$set$27,LFE1492-LFB1492
.quad L$set$27
.byte 0x0
.byte 0x4
.set L$set$28,LCFI15-LFB1492
.long L$set$28
.byte 0xe
.byte 0x10
.byte 0x86
.byte 0x2
.byte 0x4
.set L$set$29,LCFI16-LCFI15
.long L$set$29
.byte 0xd
.byte 0x6
.align 3
LEFDE13:
.constructor
.destructor
.align 1
.subsections_via_symbols
@abakulin
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I used g++ 4.6.1 and got following assembly output:
127 lines with -O0 (no optimization)
75 lines with -O1
76 lines with -O2
76 lines with -O3
In the last case only 17 out of 76 lines are actual instructions.

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