--- /dev/null
+
+/* HOW TO USE
+
+Compile test file (eg test_hello.c) to a .o
+
+It must have an entry point called "entry" immediately preceded by the
+bytes 0x11 0x22 0x33 0x44 0x55 0x66 0x77 0x88, so the entry point can
+be found.
+
+It must have ***NO RELOCATIONS*** - objdump -r file.o shows none
+
+*/
+
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "../pub/libvex_basictypes.h"
+#include "../pub/libvex_guest_x86.h"
+#include "../pub/libvex_guest_amd64.h"
+#include "../pub/libvex.h"
+
+
+static Int n_bbs_done = 0;
+
+/* For providing services. */
+static HWord serviceFn ( HWord arg1, HWord arg2 )
+{
+ switch (arg1) {
+ case 0: /* EXIT */
+ printf("---STOP---\n");
+ printf("serviceFn:EXIT\n");
+ printf("%d bbs simulated\n", n_bbs_done);
+ exit(0);
+ case 1: /* PUTC */
+ putchar(arg2);
+ return 0;
+ case 2: /* MALLOC */
+ return (HWord)malloc(arg2);
+ default:
+ assert(0);
+ }
+}
+
+
+#if defined(__i386__)
+# define VexGuestState VexGuestX86State
+# define LibVEX_Guest_initialise LibVEX_GuestX86_initialise
+# define VexArch VexArchX86
+# define VexSubArch VexSubArchX86_sse1
+# define GuestPC guest_EIP
+#else
+# error "Unknown arch"
+#endif
+
+#define TEST_FLAGS (1<<7) //|(1<<0)
+
+
+/* guest state */
+UInt gstack[50000];
+VexGuestState gst;
+VexControl vcon;
+
+/* only used for the switchback transition */
+/* i386: helper1 = &gst, helper2 = %EFLAGS */
+HWord sb_helper1 = 0;
+HWord sb_helper2 = 0;
+
+/* translation cache */
+#define N_TRANS_CACHE 100000
+#define N_TRANS_TABLE 1000
+
+ULong trans_cache[N_TRANS_CACHE];
+VexGuestExtents trans_table [N_TRANS_TABLE];
+ULong* trans_tableP[N_TRANS_TABLE];
+
+Int trans_cache_used = 0;
+Int trans_table_used = 0;
+
+static Bool chase_into_not_ok ( Addr64 dst ) { return False; }
+
+/* -------------------- */
+#if defined(__i386__)
+
+/* continue execution on the real CPU (never returns) */
+extern void switchback_asm(void);
+asm(
+"switchback_asm:\n"
+" movl sb_helper1, %eax\n" // eax = guest state ptr
+" movl 16(%eax), %esp\n" // switch stacks
+" pushl 56(%eax)\n" // push continuation addr
+" movl sb_helper2, %ebx\n" // get eflags
+" pushl %ebx\n" // eflags:CA
+" pushl 0(%eax)\n" // EAX:eflags:CA
+" movl 4(%eax), %ecx\n"
+" movl 8(%eax), %edx\n"
+" movl 12(%eax), %ebx\n"
+" movl 20(%eax), %ebp\n"
+" movl 24(%eax), %esi\n"
+" movl 28(%eax), %edi\n"
+" popl %eax\n"
+" popfl\n"
+" ret\n"
+);
+void switchback ( void )
+{
+ sb_helper1 = (HWord)&gst;
+ sb_helper2 = LibVEX_GuestX86_get_eflags(&gst);
+ switchback_asm(); // never returns
+}
+
+#else
+# error "Unknown arch (switchback)"
+#endif
+
+/* -------------------- */
+static HWord f, gp, res;
+extern void run_translation_asm(void);
+asm(
+"run_translation_asm:\n"
+" pushal\n"
+" movl gp, %ebp\n"
+" movl f, %eax\n"
+" call *%eax\n"
+" movl %eax, res\n"
+" popal\n"
+" ret\n"
+);
+
+void run_translation ( HWord translation )
+{
+ if (0)
+ printf(" run translation %p\n", (void*)translation );
+ f = translation;
+ gp = (HWord)&gst;
+ run_translation_asm();
+ gst.GuestPC = res;
+ n_bbs_done ++;
+}
+
+HWord find_translation ( Addr64 guest_addr )
+{
+ Int i;
+ HWord res;
+ if (0)
+ printf("find translation %p ... ", ULong_to_Ptr(guest_addr));
+ for (i = 0; i < trans_table_used; i++)
+ if (trans_table[i].base[0] == guest_addr)
+ break;
+ if (i == trans_table_used) {
+ if (0) printf("none\n");
+ return 0; /* not found */
+ }
+ res = (HWord)trans_tableP[i];
+ if (0) printf("%p\n", (void*)res);
+ return res;
+}
+
+#define N_TRANSBUF 5000
+static UChar transbuf[N_TRANSBUF];
+void make_translation ( Addr64 guest_addr, Bool verbose )
+{
+ VexTranslateResult tres;
+ Int trans_used, i, ws_needed;
+ assert(trans_table_used < N_TRANS_TABLE);
+ if (0)
+ printf("make translation %p\n", ULong_to_Ptr(guest_addr));
+ tres
+ = LibVEX_Translate (
+ VexArch, VexSubArch,
+ VexArch, VexSubArch,
+ ULong_to_Ptr(guest_addr), guest_addr,
+ chase_into_not_ok,
+ &trans_table[trans_table_used],
+ transbuf, N_TRANSBUF, &trans_used,
+ NULL, /* instrument1 */
+ NULL, /* instrument2 */
+ False, /* cleanup after instrument */
+ NULL, /* access checker */
+ verbose ? TEST_FLAGS : 0
+ );
+ assert(tres == VexTransOK);
+ ws_needed = (trans_used+7) / 8;
+ assert(ws_needed > 0);
+ assert(trans_cache_used + ws_needed < N_TRANS_CACHE);
+
+ for (i = 0; i < trans_used; i++) {
+ HChar* dst = ((HChar*)(&trans_cache[trans_cache_used])) + i;
+ HChar* src = (HChar*)(&transbuf[i]);
+ *dst = *src;
+ }
+
+ trans_tableP[trans_table_used] = &trans_cache[trans_cache_used];
+ trans_table_used++;
+ trans_cache_used += ws_needed;
+}
+
+
+static Int stopAfter = 0;
+static UChar* image = NULL;
+static Int imageSz = 0;
+static UChar* entry = NULL;
+
+
+__attribute__ ((noreturn))
+static
+void failure_exit ( void )
+{
+ fprintf(stdout, "VEX did failure_exit. Bye.\n");
+ exit(1);
+}
+
+static
+void log_bytes ( HChar* bytes, Int nbytes )
+{
+ fwrite ( bytes, 1, nbytes, stdout );
+}
+
+
+/* run simulated code forever (it will exit by calling
+ serviceFn(0)). */
+static void run_simulator ( void )
+{
+ static Addr64 last_guest = 0;
+ Addr64 next_guest;
+ HWord next_host;
+ while (1) {
+ if (n_bbs_done == stopAfter) {
+ printf("---begin SWITCHBACK at %d---\n", n_bbs_done);
+ if (last_guest)
+ make_translation(last_guest,True);
+ printf("--- end SWITCHBACK at %d---\n", n_bbs_done);
+ switchback();
+ assert(0); /*NOTREACHED*/
+ }
+
+ next_guest = gst.GuestPC;
+
+ if (next_guest == Ptr_to_ULong(&serviceFn)) {
+ /* "do" the function call to serviceFn */
+# if defined(__i386__)
+ {
+ HWord esp = gst.guest_ESP;
+ gst.guest_EIP = *(UInt*)(esp+0);
+ gst.guest_EAX = serviceFn( *(UInt*)(esp+4), *(UInt*)(esp+8) );
+ gst.guest_ESP = esp+4;
+ next_guest = gst.guest_EIP;
+ }
+# else
+# error "Unknown arch"
+# endif
+ }
+
+ next_host = find_translation(next_guest);
+ if (next_host == 0) {
+ make_translation(next_guest,False);
+ next_host = find_translation(next_guest);
+ assert(next_host != 0);
+ }
+ last_guest = next_guest;
+ run_translation(next_host);
+ }
+}
+
+
+static void usage ( void )
+{
+ printf("usage: switchback file.o #bbs\n");
+ exit(1);
+}
+
+int main ( Int argc, HChar** argv )
+{
+ HChar* oname;
+ FILE* f;
+ Int n, i;
+
+ struct stat buf;
+
+ if (argc != 3)
+ usage();
+
+ oname = argv[1];
+ stopAfter = atoi(argv[2]);
+
+ if (stat(oname, &buf)) {
+ printf("switchback: can't stat %s\n", oname);
+ return 1;
+ }
+
+ imageSz = (Int)buf.st_size;
+ printf("stopAfter = %d\n", stopAfter);
+ printf("file size is %d\n", imageSz);
+
+ /* Get the file aboard and find the entry point */
+ image = malloc(imageSz);
+ assert(image);
+
+ f = fopen(oname, "r");
+ assert(f);
+ n = fread(image, 1, imageSz, f);
+ assert(n == imageSz);
+ fclose(f);
+
+ assert(imageSz > 12);
+ entry = NULL;
+ for (n = 0; n < imageSz - 8; n++) {
+ if (image[n+0] == 0x11
+ && image[n+1] == 0x22
+ && image[n+2] == 0x33
+ && image[n+3] == 0x44
+ && image[n+4] == 0x55
+ && image[n+5] == 0x66
+ && image[n+6] == 0x77
+ && image[n+7] == 0x88
+ ) {
+ entry = &image[n+8];
+ break;
+ }
+ }
+
+ if (!entry) {
+ printf("switchback: can't find entry point\n");
+ exit(1);
+ }
+
+ printf("switchback: entry bytes are: ");
+ for (i = 0; i < 4; i++)
+ printf("0x%02x ", (Int)entry[i]);
+
+ LibVEX_default_VexControl(&vcon);
+ vcon.guest_max_insns=1; //50;
+ vcon.guest_chase_thresh=0;
+ LibVEX_Init( failure_exit, log_bytes, 1, False, &vcon );
+ LibVEX_Guest_initialise(&gst);
+
+ /* set up as if a call to the entry point passing serviceFn as
+ the one and only parameter */
+# if defined(__i386__)
+ gst.guest_EIP = (UInt)entry;
+ gst.guest_ESP = (UInt)&gstack[25000];
+ *(UInt*)(gst.guest_ESP+4) = (UInt)serviceFn;
+ *(UInt*)(gst.guest_ESP+0) = 0x12345678;
+# else
+# error "Unknown arch"
+# endif
+
+ printf("\n---START---\n");
+
+ run_simulator();
+
+ return 0;
+}
projects / thirdparty / valgrind.git / commitdiff
