[PATCH] libsanitizer: Fix GetPcSpBp determination of SP on 32-bit Solaris/x86

[Rainer Orth]

The latest Solaris 11.4/x86 update uncovered a libsanitizer bug that
caused one test to FAIL for 32-bit:

+FAIL: c-c++-common/asan/null-deref-1.c   -O0  output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -O1  output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -O2  output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -O2 -flto  output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -O2 -flto -flto-partition=none  
output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -O3 -g  output pattern test
+FAIL: c-c++-common/asan/null-deref-1.c   -Os  output pattern test

I've identified the problem and the fix has just landed in upstream
llvm-project:

        https://reviews.llvm.org/D83664

Tested on i386-pc-solaris2.11 on master, gcc-10 and gcc-9 branches.

Ok for all three?

        Rainer

-- 
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University


2020-07-13  Rainer Orth  <r...@cebitec.uni-bielefeld.de>

        * sanitizer_common/sanitizer_linux.cpp: Cherry-pick llvm-project
        revision f0e9b76c3500496f8f3ea7abe6f4bf801e3b41e7.


# HG changeset patch
# Parent  829b9cc5641b7899449adf14549fd4052aeea596
libsanitizer: Fix GetPcSpBp determination of SP on 32-bit Solaris/x86

diff --git a/libsanitizer/sanitizer_common/sanitizer_linux.cpp b/libsanitizer/sanitizer_common/sanitizer_linux.cpp
--- a/libsanitizer/sanitizer_common/sanitizer_linux.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_linux.cpp
@@ -2043,13 +2043,13 @@ static void GetPcSpBp(void *context, upt
 # ifndef REG_EBP
 #  define REG_EBP  6 // REG_FP
 # endif
-# ifndef REG_ESP
-#  define REG_ESP 17 // REG_SP
+# ifndef REG_UESP
+#  define REG_UESP 17 // REG_SP
 # endif
 # endif
   *pc = ucontext->uc_mcontext.gregs[REG_EIP];
   *bp = ucontext->uc_mcontext.gregs[REG_EBP];
-  *sp = ucontext->uc_mcontext.gregs[REG_ESP];
+  *sp = ucontext->uc_mcontext.gregs[REG_UESP];
 # endif
 #elif defined(__powerpc__) || defined(__powerpc64__)
   ucontext_t *ucontext = (ucontext_t*)context;