Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20200330' into staging

Improve PIE and other linkage
Fix for decodetree vs Python3 floor division operator
Fix i386 INDEX_op_dup2_vec expansion
Fix loongson multimedia condition instructions

# gpg: Signature made Tue 31 Mar 2020 04:50:15 BST
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-tcg-20200330:
  decodetree: Use Python3 floor division operator
  tcg/i386: Fix INDEX_op_dup2_vec
  target/mips: Fix loongson multimedia condition instructions
  configure: Support -static-pie if requested
  configure: Override the os default with --disable-pie
  configure: Unnest detection of -z,relro and -z,now
  configure: Always detect -no-pie toolchain support
  configure: Do not force pie=no for non-x86
  tcg: Remove softmmu code_gen_buffer fixed address
  configure: Drop adjustment of textseg

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

6 files changed, 78 insertions, 126 deletions

diff --git a/Makefile b/Makefile
index fc2808fb4b..84ef881600 100644
--- a/Makefile
+++ b/Makefile
@@ -795,7 +795,7 @@ rm -f $(MANUAL_BUILDDIR)/$1/objects.inv $(MANUAL_BUILDDIR)/$1/searchindex.js $(M
 endef
 
 distclean: clean
-	rm -f config-host.mak config-host.h* config-host.ld $(DOCS)
+	rm -f config-host.mak config-host.h* $(DOCS)
 	rm -f tests/tcg/config-*.mak
 	rm -f config-all-devices.mak config-all-disas.mak config.status
 	rm -f $(SUBDIR_DEVICES_MAK)
diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index 78914154bf..9924e66d1f 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -1043,47 +1043,20 @@ static inline void *alloc_code_gen_buffer(void)
 {
     int prot = PROT_WRITE | PROT_READ | PROT_EXEC;
     int flags = MAP_PRIVATE | MAP_ANONYMOUS;
-    uintptr_t start = 0;
     size_t size = tcg_ctx->code_gen_buffer_size;
     void *buf;
 
-    /* Constrain the position of the buffer based on the host cpu.
-       Note that these addresses are chosen in concert with the
-       addresses assigned in the relevant linker script file.  */
-# if defined(__PIE__) || defined(__PIC__)
-    /* Don't bother setting a preferred location if we're building
-       a position-independent executable.  We're more likely to get
-       an address near the main executable if we let the kernel
-       choose the address.  */
-# elif defined(__x86_64__) && defined(MAP_32BIT)
-    /* Force the memory down into low memory with the executable.
-       Leave the choice of exact location with the kernel.  */
-    flags |= MAP_32BIT;
-    /* Cannot expect to map more than 800MB in low memory.  */
-    if (size > 800u * 1024 * 1024) {
-        tcg_ctx->code_gen_buffer_size = size = 800u * 1024 * 1024;
-    }
-# elif defined(__sparc__)
-    start = 0x40000000ul;
-# elif defined(__s390x__)
-    start = 0x90000000ul;
-# elif defined(__mips__)
-#  if _MIPS_SIM == _ABI64
-    start = 0x128000000ul;
-#  else
-    start = 0x08000000ul;
-#  endif
-# endif
-
-    buf = mmap((void *)start, size, prot, flags, -1, 0);
+    buf = mmap(NULL, size, prot, flags, -1, 0);
     if (buf == MAP_FAILED) {
         return NULL;
     }
 
 #ifdef __mips__
     if (cross_256mb(buf, size)) {
-        /* Try again, with the original still mapped, to avoid re-acquiring
-           that 256mb crossing.  This time don't specify an address.  */
+        /*
+         * Try again, with the original still mapped, to avoid re-acquiring
+         * the same 256mb crossing.
+         */
         size_t size2;
         void *buf2 = mmap(NULL, size, prot, flags, -1, 0);
         switch ((int)(buf2 != MAP_FAILED)) {
diff --git a/configure b/configure
index e225a1e3ff..22870f3867 100755
--- a/configure
+++ b/configure
@@ -1067,7 +1067,6 @@ for opt do
   ;;
   --static)
     static="yes"
-    QEMU_LDFLAGS="-static $QEMU_LDFLAGS"
     QEMU_PKG_CONFIG_FLAGS="--static $QEMU_PKG_CONFIG_FLAGS"
   ;;
   --mandir=*) mandir="$optarg"
@@ -2089,11 +2088,6 @@ if test "$static" = "yes" ; then
   if test "$modules" = "yes" ; then
     error_exit "static and modules are mutually incompatible"
   fi
-  if test "$pie" = "yes" ; then
-    error_exit "static and pie are mutually incompatible"
-  else
-    pie="no"
-  fi
 fi
 
 # Unconditional check for compiler __thread support
@@ -2107,51 +2101,52 @@ if ! compile_prog "-Werror" "" ; then
 	"Thread-Local Storage (TLS). Please upgrade to a version that does."
 fi
 
-if test "$pie" = ""; then
-  case "$cpu-$targetos" in
-    i386-Linux|x86_64-Linux|x32-Linux|i386-OpenBSD|x86_64-OpenBSD)
-      ;;
-    *)
-      pie="no"
-      ;;
-  esac
-fi
-
-if test "$pie" != "no" ; then
-  cat > $TMPC << EOF
+cat > $TMPC << EOF
 
 #ifdef __linux__
 #  define THREAD __thread
 #else
 #  define THREAD
 #endif
-
 static THREAD int tls_var;
-
 int main(void) { return tls_var; }
-
 EOF
-  # check we support --no-pie first...
-  if compile_prog "-Werror -fno-pie" "-no-pie"; then
-    CFLAGS_NOPIE="-fno-pie"
-    LDFLAGS_NOPIE="-nopie"
-  fi
 
-  if compile_prog "-fPIE -DPIE" "-pie"; then
+# Check we support --no-pie first; we will need this for building ROMs.
+if compile_prog "-Werror -fno-pie" "-no-pie"; then
+  CFLAGS_NOPIE="-fno-pie"
+  LDFLAGS_NOPIE="-no-pie"
+fi
+
+if test "$static" = "yes"; then
+  if test "$pie" != "no" && compile_prog "-fPIE -DPIE" "-static-pie"; then
     QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS"
-    QEMU_LDFLAGS="-pie $QEMU_LDFLAGS"
+    QEMU_LDFLAGS="-static-pie $QEMU_LDFLAGS"
     pie="yes"
-    if compile_prog "" "-Wl,-z,relro -Wl,-z,now" ; then
-      QEMU_LDFLAGS="-Wl,-z,relro -Wl,-z,now $QEMU_LDFLAGS"
-    fi
+  elif test "$pie" = "yes"; then
+    error_exit "-static-pie not available due to missing toolchain support"
   else
-    if test "$pie" = "yes"; then
-      error_exit "PIE not available due to missing toolchain support"
-    else
-      echo "Disabling PIE due to missing toolchain support"
-      pie="no"
-    fi
+    QEMU_LDFLAGS="-static $QEMU_LDFLAGS"
+    pie="no"
   fi
+elif test "$pie" = "no"; then
+  QEMU_CFLAGS="$CFLAGS_NOPIE $QEMU_CFLAGS"
+  QEMU_LDFLAGS="$LDFLAGS_NOPIE $QEMU_LDFLAGS"
+elif compile_prog "-fPIE -DPIE" "-pie"; then
+  QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS"
+  QEMU_LDFLAGS="-pie $QEMU_LDFLAGS"
+  pie="yes"
+elif test "$pie" = "yes"; then
+  error_exit "PIE not available due to missing toolchain support"
+else
+  echo "Disabling PIE due to missing toolchain support"
+  pie="no"
+fi
+
+# Detect support for PT_GNU_RELRO + DT_BIND_NOW.
+# The combination is known as "full relro", because .got.plt is read-only too.
+if compile_prog "" "-Wl,-z,relro -Wl,-z,now" ; then
+  QEMU_LDFLAGS="-Wl,-z,relro -Wl,-z,now $QEMU_LDFLAGS"
 fi
 
 ##########################################
@@ -6498,49 +6493,6 @@ if test "$cpu" = "s390x" ; then
   fi
 fi
 
-# Probe for the need for relocating the user-only binary.
-if ( [ "$linux_user" = yes ] || [ "$bsd_user" = yes ] ) && [ "$pie" = no ]; then
-  textseg_addr=
-  case "$cpu" in
-    arm | i386 | ppc* | s390* | sparc* | x86_64 | x32)
-      # ??? Rationale for choosing this address
-      textseg_addr=0x60000000
-      ;;
-    mips)
-      # A 256M aligned address, high in the address space, with enough
-      # room for the code_gen_buffer above it before the stack.
-      textseg_addr=0x60000000
-      ;;
-  esac
-  if [ -n "$textseg_addr" ]; then
-    cat > $TMPC <<EOF
-    int main(void) { return 0; }
-EOF
-    textseg_ldflags="-Wl,-Ttext-segment=$textseg_addr"
-    if ! compile_prog "" "$textseg_ldflags"; then
-      # In case ld does not support -Ttext-segment, edit the default linker
-      # script via sed to set the .text start addr.  This is needed on FreeBSD
-      # at least.
-      if ! $ld --verbose >/dev/null 2>&1; then
-        error_exit \
-            "We need to link the QEMU user mode binaries at a" \
-            "specific text address. Unfortunately your linker" \
-            "doesn't support either the -Ttext-segment option or" \
-            "printing the default linker script with --verbose." \
-            "If you don't want the user mode binaries, pass the" \
-            "--disable-user option to configure."
-      fi
-
-      $ld --verbose | sed \
-        -e '1,/==================================================/d' \
-        -e '/==================================================/,$d' \
-        -e "s/[.] = [0-9a-fx]* [+] SIZEOF_HEADERS/. = $textseg_addr + SIZEOF_HEADERS/" \
-        -e "s/__executable_start = [0-9a-fx]*/__executable_start = $textseg_addr/" > config-host.ld
-      textseg_ldflags="-Wl,-T../config-host.ld"
-    fi
-  fi
-fi
-
 # Check that the C++ compiler exists and works with the C compiler.
 # All the QEMU_CXXFLAGS are based on QEMU_CFLAGS. Keep this at the end to don't miss any other that could be added.
 if has $cxx; then
@@ -8175,10 +8127,6 @@ if test "$gprof" = "yes" ; then
   fi
 fi
 
-if test "$target_linux_user" = "yes" || test "$target_bsd_user" = "yes" ; then
-  ldflags="$ldflags $textseg_ldflags"
-fi
-
 # Newer kernels on s390 check for an S390_PGSTE program header and
 # enable the pgste page table extensions in that case. This makes
 # the vm.allocate_pgste sysctl unnecessary. We enable this program
diff --git a/scripts/decodetree.py b/scripts/decodetree.py
index 2a8f2b6e06..46ab917807 100755
--- a/scripts/decodetree.py
+++ b/scripts/decodetree.py
@@ -1025,7 +1025,7 @@ class SizeTree:
         if extracted < self.width:
             output(ind, 'insn = ', decode_function,
                    '_load_bytes(ctx, insn, {0}, {1});\n'
-                   .format(extracted / 8, self.width / 8));
+                   .format(extracted // 8, self.width // 8));
             extracted = self.width
 
         # Attempt to aid the compiler in producing compact switch statements.
@@ -1079,7 +1079,7 @@ class SizeLeaf:
         if extracted < self.width:
             output(ind, 'insn = ', decode_function,
                    '_load_bytes(ctx, insn, {0}, {1});\n'
-                   .format(extracted / 8, self.width / 8));
+                   .format(extracted // 8, self.width // 8));
             extracted = self.width
         output(ind, 'return insn;\n')
 # end SizeLeaf
diff --git a/target/mips/translate.c b/target/mips/translate.c
index d745bd2803..25b595a17d 100644
--- a/target/mips/translate.c
+++ b/target/mips/translate.c
@@ -5529,6 +5529,7 @@ static void gen_loongson_multimedia(DisasContext *ctx, int rd, int rs, int rt)
 {
     uint32_t opc, shift_max;
     TCGv_i64 t0, t1;
+    TCGCond cond;
 
     opc = MASK_LMI(ctx->opcode);
     switch (opc) {
@@ -5862,14 +5863,39 @@ static void gen_loongson_multimedia(DisasContext *ctx, int rd, int rs, int rt)
 
     case OPC_SEQU_CP2:
     case OPC_SEQ_CP2:
+        cond = TCG_COND_EQ;
+        goto do_cc_cond;
+        break;
     case OPC_SLTU_CP2:
+        cond = TCG_COND_LTU;
+        goto do_cc_cond;
+        break;
     case OPC_SLT_CP2:
+        cond = TCG_COND_LT;
+        goto do_cc_cond;
+        break;
     case OPC_SLEU_CP2:
+        cond = TCG_COND_LEU;
+        goto do_cc_cond;
+        break;
     case OPC_SLE_CP2:
-        /*
-         * ??? Document is unclear: Set FCC[CC].  Does that mean the
-         * FD field is the CC field?
-         */
+        cond = TCG_COND_LE;
+    do_cc_cond:
+        {
+            int cc = (ctx->opcode >> 8) & 0x7;
+            TCGv_i64 t64 = tcg_temp_new_i64();
+            TCGv_i32 t32 = tcg_temp_new_i32();
+
+            tcg_gen_setcond_i64(cond, t64, t0, t1);
+            tcg_gen_extrl_i64_i32(t32, t64);
+            tcg_gen_deposit_i32(fpu_fcr31, fpu_fcr31, t32,
+                                get_fp_bit(cc), 1);
+
+            tcg_temp_free_i32(t32);
+            tcg_temp_free_i64(t64);
+        }
+        goto no_rd;
+        break;
     default:
         MIPS_INVAL("loongson_cp2");
         generate_exception_end(ctx, EXCP_RI);
@@ -5878,6 +5904,7 @@ static void gen_loongson_multimedia(DisasContext *ctx, int rd, int rs, int rt)
 
     gen_store_fpr64(ctx, t0, rd);
 
+no_rd:
     tcg_temp_free_i64(t0);
     tcg_temp_free_i64(t1);
 }
diff --git a/tcg/i386/tcg-target.inc.c b/tcg/i386/tcg-target.inc.c
index 223dba9c8c..7f61eeedd0 100644
--- a/tcg/i386/tcg-target.inc.c
+++ b/tcg/i386/tcg-target.inc.c
@@ -2855,9 +2855,13 @@ static void tcg_out_vec_op(TCGContext *s, TCGOpcode opc,
         goto gen_simd;
 #if TCG_TARGET_REG_BITS == 32
     case INDEX_op_dup2_vec:
-        /* Constraints have already placed both 32-bit inputs in xmm regs.  */
-        insn = OPC_PUNPCKLDQ;
-        goto gen_simd;
+        /* First merge the two 32-bit inputs to a single 64-bit element. */
+        tcg_out_vex_modrm(s, OPC_PUNPCKLDQ, a0, a1, a2);
+        /* Then replicate the 64-bit elements across the rest of the vector. */
+        if (type != TCG_TYPE_V64) {
+            tcg_out_dup_vec(s, type, MO_64, a0, a0);
+        }
+        break;
 #endif
     case INDEX_op_abs_vec:
         insn = abs_insn[vece];