1 /* 2 3 2006-05-21: vex r1619 finally causes the x86->IR front end to state 4 exactly the %eflags dataflow surrounding 'cmpb $0, ... ; js ..' 5 and so memcheck no longer gives a false positive on this test. 6 7 ----------- 8 9 (original comments) 10 Assembly derived from the following program compiled with -O2. 11 This fools Valgrind, causing it to give a false error. 12 13 #include <stdio.h> 14 15 struct Foo 16 { 17 int a1 : 1; 18 int a2 : 1; 19 int a3 : 1; 20 int a4 : 1; 21 int a5 : 1; 22 int a6 : 1; 23 int a7 : 1; 24 int bleh : 1; 25 }; 26 27 struct Foo* foo; 28 29 void set() 30 { 31 foo->bleh = 1; 32 } 33 34 void get() 35 { 36 if ( foo->bleh == 0 ) 37 printf( "blieb\n" ); 38 } 39 40 int main() 41 { 42 foo = malloc(sizeof(struct Foo)); 43 set(); 44 45 get(); 46 47 return 0; 48 } 49 50 */ 51 52 #include "tests/asm.h" 53 54 .file "tronical.c" 55 #if defined(VGO_linux) || defined(VGO_solaris) 56 .version "01.01" 57 #endif 58 gcc2_compiled.: 59 .text 60 .align 4 61 .globl set 62 set: 63 pushl %ebp 64 movl foo, %eax 65 orb $128, (%eax) 66 movl %esp, %ebp 67 popl %ebp 68 ret 69 .Lfe1: 70 .LC0: 71 .ascii "blieb\n" 72 .text 73 .align 4 74 .globl get 75 get: 76 pushl %ebp 77 movl %esp, %ebp 78 subl $8, %esp 79 movl foo, %eax 80 cmpb $0, (%eax) 81 js .L4 82 subl $12, %esp 83 pushl $.LC0 84 call VG_SYM_ASM(printf) 85 addl $16, %esp 86 .L4: 87 leave 88 ret 89 .Lfe2: 90 .align 4 91 .globl VG_SYM_ASM(main) 92 VG_SYM_ASM(main): 93 pushl %ebp 94 movl %esp, %ebp 95 subl $20, %esp 96 pushl $4 97 call VG_SYM_ASM(malloc) 98 movl %eax, foo 99 call set 100 call get 101 xorl %eax, %eax 102 leave 103 ret 104 .Lfe3: 105 .comm foo,4,4 106 .ident "GCC: (GNU) 2.96 20000731 (Red Hat Linux 7.1 2.96-98)" 107
