commit f1ff8597ef9c37ff1a853411b9e3be1696c36d92

Author: Philippe Waroquiers <philippe.waroquiers@skynet.be>

Date:   Tue Sep 19 23:17:48 2017 +0200

    Implement static TLS code for more platforms

    gdbserver_tests/hgtls is failing on a number of platforms

    as it looks like static tls handling is now needed.

    So, omplement static tls for a few more platforms.

    The formulas that are platform dependent are somewhat wild guesses

    obtained with trial and errors.

    Note that arm/arm64/ppc32 are not (yet) done

diff --git a/coregrind/m_gdbserver/target.c b/coregrind/m_gdbserver/target.c

index 10e52fc..1f03c12 100644

--- a/coregrind/m_gdbserver/target.c

+++ b/coregrind/m_gdbserver/target.c

@@ -712,6 +712,7 @@ Bool valgrind_get_tls_addr (ThreadState *tst,

    // Check we can read the modid

    CHECK_DEREF(lm+lm_modid_offset, sizeof(unsigned long int), "link_map modid");

    modid = *(unsigned long int *)(lm+lm_modid_offset);

+   dlog (2, "tid %u modid %lu\n", tst->tid, modid);

    // Check we can access the dtv entry for modid

    CHECK_DEREF(dtv + 2 * modid, sizeof(CORE_ADDR), "dtv[2*modid]");

@@ -719,7 +720,6 @@ Bool valgrind_get_tls_addr (ThreadState *tst,

    // Compute the base address of the tls block.

    *tls_addr = *(dtv + 2 * modid);

-#if defined(VGA_mips32) || defined(VGA_mips64)

    if (*tls_addr & 1) {

       /* This means that computed address is not valid, most probably

          because given module uses Static TLS.

@@ -731,17 +731,24 @@ Bool valgrind_get_tls_addr (ThreadState *tst,

       CORE_ADDR tls_offset_addr;

       PtrdiffT tls_offset;

-      dlog(1, "computing tls_addr using static TLS\n");

+      dlog(2, "tls_addr (%p & 1) => computing tls_addr using static TLS\n",

+           (void*) *tls_addr);

       /* Assumes that tls_offset is placed right before tls_modid.

          To check the assumption, start a gdb on none/tests/tls and do:

-         p &((struct link_map*)0x0)->l_tls_modid

-         p &((struct link_map*)0x0)->l_tls_offset */

+           p &((struct link_map*)0x0)->l_tls_modid

+           p &((struct link_map*)0x0)->l_tls_offset

+         Instead of assuming this, we could calculate this similarly to

+         lm_modid_offset, by extending getplatformoffset to support querying

+         more than one offset.

+      */

       tls_offset_addr = lm + lm_modid_offset - sizeof(PtrdiffT);

       // Check we can read the tls_offset.

       CHECK_DEREF(tls_offset_addr, sizeof(PtrdiffT), "link_map tls_offset");

       tls_offset = *(PtrdiffT *)(tls_offset_addr);

+      dlog(2, "tls_offset_addr %p tls_offset %ld\n",

+           (void*)tls_offset_addr, (long)tls_offset);

       /* Following two values represent platform dependent constants

          NO_TLS_OFFSET and FORCED_DYNAMIC_TLS_OFFSET, respectively. */

@@ -751,9 +758,18 @@ Bool valgrind_get_tls_addr (ThreadState *tst,

       }

       // This calculation is also platform dependent.

+#if defined(VGA_mips32) || defined(VGA_mips64)

       *tls_addr = ((CORE_ADDR)dtv_loc + 2 * sizeof(CORE_ADDR) + tls_offset);

-   }

+#elif defined(VGA_ppc64be) || defined(VGA_ppc64le)

+      *tls_addr = ((CORE_ADDR)dtv_loc + sizeof(CORE_ADDR) + tls_offset);

+#elif defined(VGA_x86) || defined(VGA_amd64) || defined(VGA_s390x)

+      *tls_addr = (CORE_ADDR)dtv_loc - tls_offset - sizeof(CORE_ADDR);

+#else

+      // ppc32, arm, arm64

+      dlog(0, "target.c is missing platform code for static TLS\n");

+      return False;

 #endif

+   }

    // Finally, add tls variable offset to tls block base address.

    *tls_addr += offset;