Remove host endianness info from TargetData and

put it in a new header System/Host.h instead.
Instead of getting the endianness from configure,
calculate it directly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44959 91177308-0d34-0410-b5e6-96231b3b80d8

autoconf/configure.ac

@@ -227,10 +227,7 @@ dnl Define a substitution, ARCH, for the target architecture
 AC_SUBST(ARCH,$llvm_cv_target_arch)
 
 dnl Check for the endianness of the target
-AC_C_BIGENDIAN([AC_SUBST([ENDIAN],[big]),
+AC_C_BIGENDIAN(AC_SUBST([ENDIAN],[big]),AC_SUBST([ENDIAN],[little]))
-                AC_DEFINE([MSB_FIRST], [1], [Define if this target is big endian])],
-               [AC_SUBST([ENDIAN],[little]),
-                AC_DEFINE([LSB_FIRST], [1], [Define if this target is little endian])])
 
 dnl Check for build platform executable suffix if we're crosscompiling
 if test "$cross_compiling" = yes; then

configure

@@ -828,6 +828,7 @@ NOLINKALL
 LLVM_ON_UNIX
 LLVM_ON_WIN32
 ARCH
+ENDIAN
 CC
 CFLAGS
 LDFLAGS
@@ -838,7 +839,6 @@ OBJEXT
 CPP
 GREP
 EGREP
-ENDIAN
 LLVM_CROSS_COMPILING
 BUILD_CC
 BUILD_EXEEXT
@@ -4183,19 +4183,9 @@ echo "${ECHO_T}$ac_cv_c_bigendian" >&6; }
 case $ac_cv_c_bigendian in
   yes)
     ENDIAN=big
-,
-
-cat >>confdefs.h <<\_ACEOF
-#define MSB_FIRST 1
-_ACEOF
  ;;
   no)
     ENDIAN=little
-,
-
-cat >>confdefs.h <<\_ACEOF
-#define LSB_FIRST 1
-_ACEOF
  ;;
   *)
     { { echo "$as_me:$LINENO: error: unknown endianness
@@ -9881,7 +9871,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 9884 "configure"
+#line 9874 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11816,7 +11806,7 @@ ia64-*-hpux*)
   ;;
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 11819 "configure"' > conftest.$ac_ext
+  echo '#line 11809 "configure"' > conftest.$ac_ext
   if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
@@ -13456,11 +13446,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:13459: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:13449: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:13463: \$? = $ac_status" >&5
+   echo "$as_me:13453: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -13724,11 +13714,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:13727: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:13717: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:13731: \$? = $ac_status" >&5
+   echo "$as_me:13721: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -13828,11 +13818,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:13831: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:13821: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:13835: \$? = $ac_status" >&5
+   echo "$as_me:13825: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -16136,7 +16126,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 16139 "configure"
+#line 16129 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -16236,7 +16226,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 16239 "configure"
+#line 16229 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -18572,11 +18562,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18575: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18565: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:18579: \$? = $ac_status" >&5
+   echo "$as_me:18569: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -18676,11 +18666,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18679: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18669: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:18683: \$? = $ac_status" >&5
+   echo "$as_me:18673: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -20246,11 +20236,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:20249: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:20239: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:20253: \$? = $ac_status" >&5
+   echo "$as_me:20243: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -20350,11 +20340,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:20353: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:20343: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:20357: \$? = $ac_status" >&5
+   echo "$as_me:20347: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -22553,11 +22543,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:22556: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:22546: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:22560: \$? = $ac_status" >&5
+   echo "$as_me:22550: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -22821,11 +22811,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:22824: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:22814: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:22828: \$? = $ac_status" >&5
+   echo "$as_me:22818: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -22925,11 +22915,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:22928: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:22918: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:22932: \$? = $ac_status" >&5
+   echo "$as_me:22922: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -32769,6 +32759,7 @@ NOLINKALL!$NOLINKALL$ac_delim
 LLVM_ON_UNIX!$LLVM_ON_UNIX$ac_delim
 LLVM_ON_WIN32!$LLVM_ON_WIN32$ac_delim
 ARCH!$ARCH$ac_delim
+ENDIAN!$ENDIAN$ac_delim
 CC!$CC$ac_delim
 CFLAGS!$CFLAGS$ac_delim
 LDFLAGS!$LDFLAGS$ac_delim
@@ -32779,7 +32770,6 @@ OBJEXT!$OBJEXT$ac_delim
 CPP!$CPP$ac_delim
 GREP!$GREP$ac_delim
 EGREP!$EGREP$ac_delim
-ENDIAN!$ENDIAN$ac_delim
 LLVM_CROSS_COMPILING!$LLVM_CROSS_COMPILING$ac_delim
 BUILD_CC!$BUILD_CC$ac_delim
 BUILD_EXEEXT!$BUILD_EXEEXT$ac_delim

include/llvm/Config/config.h.in

@@ -494,9 +494,6 @@
 /* Installation prefix directory */
 #undef LLVM_PREFIX
 
-/* Define if this target is little endian */
-#undef LSB_FIRST
-
 /* Define if the OS needs help to load dependent libraries for dlopen(). */
 #undef LTDL_DLOPEN_DEPLIBS
 
@@ -514,9 +511,6 @@
 /* Define to the system default library search path. */
 #undef LTDL_SYSSEARCHPATH
 
-/* Define if this target is big endian */
-#undef MSB_FIRST
-
 /* Define if /dev/zero should be used when mapping RWX memory, or undefine if
    its not necessary */
 #undef NEED_DEV_ZERO_FOR_MMAP

include/llvm/System/Host.h

@@ -0,0 +1,36 @@
+//===- llvm/System/Host.h - Host machine characteristics --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Duncan Sands and is distributed under the
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Methods for querying the nature of the host machine.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SYSTEM_HOST_H
+#define LLVM_SYSTEM_HOST_H
+
+namespace llvm {
+namespace sys {
+
+  inline bool littleEndianHost() {
+    union {
+      int i;
+      char c;
+    };
+    i = 1;
+    return c;
+  }
+
+  inline bool bigEndianHost() {
+    return !littleEndianHost();
+  }
+
+}
+}
+
+#endif

include/llvm/Target/TargetData.h

@@ -142,10 +142,6 @@ public:
   bool          isLittleEndian()       const { return     LittleEndian; }
   bool          isBigEndian()          const { return    !LittleEndian; }
 
-  /// Host endianness.
-  bool hostIsLittleEndian() const;
-  bool hostIsBigEndian() const { return !hostIsLittleEndian(); }
-
   /// getStringRepresentation - Return the string representation of the
   /// TargetData.  This representation is in the same format accepted by the
   /// string constructor above.

lib/ExecutionEngine/ExecutionEngine.cpp

@@ -23,6 +23,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/MutexGuard.h"
 #include "llvm/System/DynamicLibrary.h"
+#include "llvm/System/Host.h"
 #include "llvm/Target/TargetData.h"
 #include <math.h>
 using namespace llvm;
@@ -637,7 +638,7 @@ void ExecutionEngine::StoreValueToMemory(const GenericValue &Val, GenericValue *
     uint8_t *Src = (uint8_t *)Val.IntVal.getRawData();
     uint8_t *Dst = (uint8_t *)Ptr;
 
-    if (getTargetData()->hostIsLittleEndian())
+    if (sys::littleEndianHost())
       // Little-endian host - the source is ordered from LSB to MSB.
       // Order the destination from LSB to MSB: Do a straight copy.
       memcpy(Dst, Src, StoreBytes);
@@ -698,7 +699,7 @@ void ExecutionEngine::LoadValueFromMemory(GenericValue &Result,
     uint8_t *Src = (uint8_t *)Ptr;
     uint8_t *Dst = (uint8_t *)Result.IntVal.getRawData();
 
-    if (getTargetData()->hostIsLittleEndian())
+    if (sys::littleEndianHost())
       // Little-endian host - the destination must be ordered from LSB to MSB.
       // The source is ordered from LSB to MSB: Do a straight copy.
       memcpy(Dst, Src, LoadBytes);

lib/Target/TargetData.cpp

@@ -25,7 +25,6 @@
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringExtras.h"
-#include "llvm/Config/config.h"
 #include <algorithm>
 #include <cstdlib>
 #include <sstream>
@@ -133,14 +132,6 @@ const TargetAlignElem TargetData::InvalidAlignmentElem =
 //                       TargetData Class Implementation
 //===----------------------------------------------------------------------===//
 
-bool TargetData::hostIsLittleEndian() const {
-#ifdef LSB_FIRST
-  return true;
-#else
-  return false;
-#endif
-}
-
 /*!
  A TargetDescription string consists of a sequence of hyphen-delimited
  specifiers for target endianness, pointer size and alignments, and various