Another shadow memory test. This one does a huge number of loads and

stores of char/short/int/int64/double at random offsets and hence
alignments in an array.  It does it in a way in which the computation
just computes the expected V bits, and hence can check whether these
seem correct.



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@5811

memcheck/tests/Makefile.am

@@ -92,6 +92,7 @@ EXTRA_DIST = $(noinst_SCRIPTS) \
 	realloc2.stderr.exp realloc2.vgtest \
 	realloc3.stderr.exp realloc3.vgtest \
 	sh-mem.stderr.exp sh-mem.vgtest \
+	sh-mem-random.stderr.exp sh-mem-random.vgtest \
 	sigaltstack.stderr.exp sigaltstack.vgtest \
 	sigkill.stderr.exp sigkill.stderr.exp2 sigkill.stderr.exp3 sigkill.vgtest \
 	signal2.stderr.exp signal2.stdout.exp signal2.vgtest \
@@ -149,7 +150,7 @@ check_PROGRAMS = \
 	pipe pointer-trace \
 	post-syscall \
 	realloc1 realloc2 realloc3 \
-	sh-mem \
+	sh-mem sh-mem-random \
 	sigaltstack signal2 sigprocmask sigkill \
 	stack_changes stack_switch strchr str_tester \
 	supp_unknown supp1 supp2 suppfree \

memcheck/tests/sh-mem-random.c

@@ -0,0 +1,239 @@
+// This program is a thorough test of the LOADVn/STOREVn shadow memory
+// operations.
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include "memcheck/memcheck.h"
+
+// All the sizes here are in *bytes*, not bits.
+
+typedef unsigned char        U1;
+typedef unsigned short       U2;
+typedef unsigned int         U4;
+typedef unsigned long long   U8;
+
+typedef float                F4;
+typedef double               F8;
+
+#define PAGE_SIZE 4096ULL
+
+
+// XXX: should check the error cases for SET/GET_VBITS also
+
+// For the byte 'x', build a value of 'size' bytes from that byte, eg:
+//   size 1 --> x
+//   size 2 --> xx
+//   size 4 --> xxxx
+//   size 8 --> xxxxxxxx
+// where the 0 bits are seen by Memcheck as defined, and the 1 bits are
+// seen as undefined (ie. the value of each bit matches its V bit, ie. the
+// resulting value is the same as its metavalue).
+//
+U8 build(int size, U1 byte)
+{
+   int i;
+   U8 mask = 0;
+   U8 shres;
+   U8 res = 0xffffffffffffffffULL, res2;
+   VALGRIND_MAKE_WRITABLE(&res, 8);
+   assert(1 == size || 2 == size || 4 == size || 8 == size);
+
+   for (i = 0; i < size; i++) {
+      mask <<= 8;
+      mask |= (U8)byte;
+   }
+
+   res &= mask;      
+   
+   // res is now considered partially defined, but we know exactly what its
+   // value is (it happens to be the same as its metavalue).
+   
+   VALGRIND_GET_VBITS(&res, &shres, 8);
+   res2 = res;
+   VALGRIND_MAKE_READABLE(&res2, 8);      // avoid the 'undefined' warning
+   assert(res2 == shres);
+   return res;
+}
+
+U1 make_defined ( U1 x )
+{
+   volatile U1 xx = x;
+   VALGRIND_MAKE_READABLE(&xx, 1);
+   return xx;
+}
+
+void check(U1* arr, int n, char* who)
+{
+   int i;
+   U1* shadow = malloc(n);
+   U1 arr_i;
+   U8 sum = 0;
+   VALGRIND_GET_VBITS(arr, shadow, n);
+   for (i = 0; i < n; i++) {
+      arr_i = make_defined(arr[i]);
+      if (arr_i != shadow[i]) {
+          fprintf(stderr, "\n\nFAILURE: %s, byte %d -- "
+                          "is 0x%x, should be 0x%x\n\n",
+                          who, i, shadow[i], arr[i]);
+          exit(1);
+      }
+      sum += (U8)arr_i;
+   }
+   free(shadow);
+   printf("test passed, sum = %llu (%9.5f per byte)\n", 
+	  sum, (F8)sum / (F8)n);
+}
+
+static inline U4 randomU4 ( void )
+{
+   static U4 n = 0;
+   /* From "Numerical Recipes in C" 2nd Edition */
+   n = 1664525UL * n + 1013904223UL;
+   return n;
+}
+
+static inline U1 randomU1 ( void )
+{
+   return 0xFF & (randomU4() >> 13);
+}
+
+#define N_BYTES  300000
+#define N_EVENTS (5 * N_BYTES)
+
+
+void do_test_at ( U1* arr )
+{
+   int i;
+
+   U4 mv1 = 0, mv2 = 0, mv4 = 0, mv8 = 0, mv4f = 0, mv8f = 0;
+
+   /* Fill arr with random bytes whose shadows match them. */
+   printf("-------- arr = %p\n", arr);
+
+   printf("initialising\n");
+   for (i = 0; i < N_BYTES; i++)
+      arr[i] = (U1)build(1, randomU1());
+
+   printf("post-initialisation check\n");
+   check(arr, N_BYTES, "after initialisation");
+
+   /* Now do huge numbers of memory copies. */
+   printf("doing copies\n");
+   for (i = 0; i < N_EVENTS; i++) {
+      U4 ty, src, dst;
+      ty  = (randomU4() >> 13) % 5;
+     tryagain:
+      src = (randomU4() >>  1) % N_BYTES;
+      dst = (randomU4() >>  3) % N_BYTES;
+      switch (ty) {
+         case 0: { // U1
+            *(U1*)(arr+dst) = *(U1*)(arr+src);
+	    mv1++;
+            break;
+         }
+         case 1: { // U2
+            if (src+2 >= N_BYTES || dst+2 >= N_BYTES) 
+               goto tryagain;
+            *(U2*)(arr+dst) = *(U2*)(arr+src);
+	    mv2++;
+            break;
+         }
+         case 2: { // U4
+            if (src+4 >= N_BYTES || dst+4 >= N_BYTES) 
+               goto tryagain;
+            *(U4*)(arr+dst) = *(U4*)(arr+src);
+	    mv4++;
+            break;
+         }
+         case 3: { // U8
+            if (src+8 >= N_BYTES || dst+8 >= N_BYTES) 
+               goto tryagain;
+            *(U8*)(arr+dst) = *(U8*)(arr+src);
+	    mv8++;
+            break;
+         }
+         /* Don't bother with 32-bit floats.  These cause
+            horrible complications, as discussed in sh-mem.c. */
+         /*
+         case 4: { // F4
+            if (src+4 >= N_BYTES || dst+4 >= N_BYTES) 
+               goto tryagain;
+            *(F4*)(arr+dst) = *(F4*)(arr+src);
+	    mv4f++;
+            break;
+         }
+         */
+         case 4: { // F8
+            if (src+8 >= N_BYTES || dst+8 >= N_BYTES) 
+               goto tryagain;
+            *(F8*)(arr+dst) = *(F8*)(arr+src);
+	    mv8f++;
+            break;
+         }
+         default:
+	   fprintf(stderr, "sh-mem-random: bad size\n");
+	   exit(0);
+      }
+   }
+
+   printf("final check\n");
+   check(arr, N_BYTES, "final check");
+
+   printf("counts 1/2/4/8/F4/F8: %d %d %d %d %d %d\n", 
+          mv1, mv2, mv4, mv8, mv4f, mv8f);
+}
+
+
+
+int main(void)
+{
+   U1* arr;
+
+   if (0 == RUNNING_ON_VALGRIND) {
+      fprintf(stderr, "error: this program only works when run under Valgrind\n");
+      exit(1);
+   }
+
+   printf("-------- testing non-auxmap range --------\n");
+
+   arr = malloc(N_BYTES);
+   assert(arr);
+   do_test_at(arr);
+   free(arr);
+
+   if (sizeof(void*) == 8) {
+      // 64-bit platform.
+      int tries;
+      int nbytes_p;
+      U1* huge_addr = (U1*)0x6600000000;  // 408GB
+      // Note, kernel 2.6.? on Athlon64 refuses fixed mmap requests
+      // at above 512GB.
+
+      printf("-------- testing auxmap range --------\n");
+
+      nbytes_p = (N_BYTES + PAGE_SIZE) & ~(PAGE_SIZE-1);
+
+      for (tries = 0; tries < 10; tries++) {
+         arr = mmap(huge_addr, nbytes_p, PROT_READ|PROT_WRITE, 
+                    MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, 0,0);
+	 if (arr != MAP_FAILED)
+            break;
+	 // hmm. fudge the address and try again.
+         huge_addr += (randomU4() & ~(PAGE_SIZE-1));
+      }
+
+      if (tries >= 10) {
+	   fprintf(stderr, "sh-mem-random: can't mmap hi-mem\n");
+	   exit(0);
+      }
+      assert(arr != MAP_FAILED);
+
+      do_test_at(arr);
+   }
+
+   return 0;
+
+}

memcheck/tests/sh-mem-random.stdout.exp

@@ -0,0 +1,9 @@
+-------- testing non-auxmap range --------
+-------- arr = 0x415b028
+initialising
+post-initialisation check
+test passed, sum = 38338686 (127.79562 per byte)
+doing copies
+final check
+test passed, sum = 38583755 (128.61252 per byte)
+counts 1/2/4/8/F4/F8: 300249 300934 299432 299394 0 299991

memcheck/tests/sh-mem-random.vgtest

@@ -0,0 +1,2 @@
+prog: sh-mem-random
+vgopts: -q