[compiler-rt] [llvm] [test][msan] Precommit tests for vararg improvements (PR #72612)

[Thurston Dang via llvm-commits]

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@@ -0,0 +1,256 @@
+// Check that shadow of retrived value from va_list matches the shadow of passed value.
+
+// Without -fno-sanitize-memory-param-retval we can't even pass poisoned values.
+// RUN: %clangxx_msan -fno-sanitize-memory-param-retval -fsanitize-memory-track-origins=0 -O3 %s -o %t
+
+// Nothing works yet.
+// XFAIL: *
+
+#include <sanitizer/msan_interface.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#define DEBUG_TEST 0
+
+#if DEBUG_TEST
+__attribute__((noinline, no_sanitize("memory"))) void
+printb(const void *p, size_t n, int line, int align) {
+  fprintf(stderr, "\n%p at line %d: \n", p, line);
+  for (int i = 0; i < n;) {
+    fprintf(stderr, "%p: ", (void *)(((uint8_t *)p) + i));
+    for (int j = 0; j < align; ++i, ++j)
+      fprintf(stderr, "%02x ", ((uint8_t *)p)[i]);
+    fprintf(stderr, "\n");
+  }
+}
+
+struct my_va_list {
+#  ifdef __ARM_ARCH_ISA_A64
+  void *stack;
+  void *gr_top;
+  void *vr_top;
+  int gr_offs;
+  int vr_offs;
+#  else
+  unsigned int gp_offset;
+  unsigned int fp_offset;
+  void *overflow_arg_area;
+  void *reg_save_area;
+#  endif
+};
+
+__attribute__((noinline, no_sanitize("memory"))) void printva(const void *p,
+                                                              int line) {
+  my_va_list *pp = (my_va_list *)p;
+#  ifdef __ARM_ARCH_ISA_A64
+  fprintf(stderr,
+          "\nva %p at line %d: stack : %p\n gr_top: %p\n vr_top: %p\n gr_offs: "
+          "%d\n "
+          "vr_offs: %d\n",
+          p, line, pp->stack, pp->gr_top, pp->vr_top, pp->gr_offs, pp->vr_offs);
+
+  printb((char *)pp->gr_top + pp->gr_offs, -pp->gr_offs, __LINE__, 8);
+  printb((char *)pp->vr_top + pp->vr_offs, -pp->vr_offs, __LINE__, 16);
+  printb((char *)pp->stack, 256, __LINE__, 8);
+#  else
+  fprintf(stderr,
+          "\nva %p at line %d:\n gp_offset: %u\n fp_offset: %u\n "
+          "overflow_arg_area: %p\n reg_save_area: %p\n\n",
+          p, line, pp->gp_offset, pp->fp_offset, pp->overflow_arg_area,
+          pp->reg_save_area);
+
+  printb((char *)pp->reg_save_area + pp->gp_offset,
+         pp->fp_offset - pp->gp_offset, __LINE__, 8);
+  printb((char *)pp->reg_save_area + pp->fp_offset, 128, __LINE__, 16);
+  printb((char *)pp->overflow_arg_area, 256, __LINE__, 8);
+#  endif
+}
+
+__attribute__((noinline, no_sanitize("memory"))) void printtls(int line) {
+  uint8_t tmp[kMsanParamTlsSize];
+  for (int i = 0; i < kMsanParamTlsSize; ++i)
+    tmp[i] = __msan_va_arg_tls[i];
+  fprintf(stderr, "\nTLS at line %d: ", line);
+  for (int i = 0; i < kMsanParamTlsSize;) {
+    fprintf(stderr, "\n");
+    for (int j = 0; j < 16; ++i, ++j)
+      fprintf(stderr, "%02x ", tmp[i]);
+  }
+
+  fprintf(stderr, "\n");
+}
+#endif
----------------
thurstond wrote:

Please add `// DEBUG_TEST`

https://github.com/llvm/llvm-project/pull/72612