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 .version "01.01" 56 gcc2_compiled.: 57 .text 58 .align 4 59 .globl set 60 set: 61 pushl %ebp 62 movl foo, %eax 63 orb $128, (%eax) 64 movl %esp, %ebp 65 popl %ebp 66 ret 67 .Lfe1: 68 .LC0: 69 .ascii "blieb\n" 70 .text 71 .align 4 72 .globl get 73 get: 74 pushl %ebp 75 movl %esp, %ebp 76 subl $8, %esp 77 movl foo, %eax 78 cmpb $0, (%eax) 79 js .L4 80 subl $12, %esp 81 pushl $.LC0 82 call VG_SYM_ASM(printf) 83 addl $16, %esp 84 .L4: 85 leave 86 ret 87 .Lfe2: 88 .align 4 89 .globl VG_SYM_ASM(main) 90 VG_SYM_ASM(main): 91 pushl %ebp 92 movl %esp, %ebp 93 subl $20, %esp 94 pushl $4 95 call VG_SYM_ASM(malloc) 96 movl %eax, foo 97 call set 98 call get 99 xorl %eax, %eax 100 leave 101 ret 102 .Lfe3: 103 .comm foo,4,4 104 .ident "GCC: (GNU) 2.96 20000731 (Red Hat Linux 7.1 2.96-98)" 105
