Extensive modifications to use ELF format as default.

(LIB_SPEC): Don't use libc_p.a for -p. don't use libg.a unless for -ggdb.
(LINUX_DEFAULT_ELF): Defined.

From-SVN: r9256

1 files changed, 174 insertions, 76 deletions

diff --git a/gcc/config/i386/linux.h b/gcc/config/i386/linux.h
index 79d7333..3238d44 100644
--- a/gcc/config/i386/linux.h
+++ b/gcc/config/i386/linux.h
@@ -1,6 +1,7 @@
-/* Definitions for Intel 386 running Linux
-   Copyright (C) 1992, 1994 Free Software Foundation, Inc.
-   Contributed by H.J. Lu (hjl@nynexst.com)
+/* Definitions for Intel 386 running Linux with ELF format
+   Copyright (C) 1994, 1995 Free Software Foundation, Inc.
+   Contributed by Eric Youngdale.
+   Modified for stabs-in-ELF by H.J. Lu.
 
 This file is part of GNU CC.
 
@@ -18,95 +19,192 @@ You should have received a copy of the GNU General Public License
 along with GNU CC; see the file COPYING.  If not, write to
 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
-#if 0	/* The FSF has fixed the known bugs. But ....... */
-
-/* Linux has a hacked gas 1.38.1, which can handle repz, repnz
- and fildll.  */
-
-#define GOOD_GAS
-#endif
-
-/* Don't assume anything about the header files. */
-#define NO_IMPLICIT_EXTERN_C
-
-/* This is tested by i386/gas.h.  */
-#define YES_UNDERSCORES
-
-#ifndef LINUX_ELF
-#include "i386/gstabs.h"
-#endif
-
-/* Specify predefined symbols in preprocessor.  */
-
-#undef CPP_PREDEFINES
-#define CPP_PREDEFINES "-Dunix -Di386 -Dlinux -Asystem(unix) -Asystem(posix) -Acpu(i386) -Amachine(i386)"
-
-#undef CPP_SPEC
-#if TARGET_CPU_DEFAULT == 2
-#define CPP_SPEC "%{!m386:-D__i486__} %{posix:-D_POSIX_SOURCE}"
-#else
-#define CPP_SPEC "%{m486:-D__i486__} %{posix:-D_POSIX_SOURCE}"
-#endif
+#define LINUX_DEFAULT_ELF
+
+/* A lie, I guess, but the general idea behind linux/ELF is that we are
+   supposed to be outputting something that will assemble under SVr4.
+   This gets us pretty close.  */
+#include "i386/i386.h"	/* Base i386 target machine definitions */
+#include "i386/att.h"	/* Use the i386 AT&T assembler syntax */
+#include "linux.h"	/* some common stuff */
+
+#undef TARGET_VERSION
+#define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)");
+
+/* The svr4 ABI for the i386 says that records and unions are returned
+   in memory.  */
+#undef DEFAULT_PCC_STRUCT_RETURN
+#define DEFAULT_PCC_STRUCT_RETURN 1
+
+/* This is how to output an element of a case-vector that is relative.
+   This is only used for PIC code.  See comments by the `casesi' insn in
+   i386.md for an explanation of the expression this outputs. */
+#undef ASM_OUTPUT_ADDR_DIFF_ELT
+#define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, VALUE, REL) \
+  fprintf (FILE, "\t.long _GLOBAL_OFFSET_TABLE_+[.-%s%d]\n", LPREFIX, VALUE)
+
+/* Indicate that jump tables go in the text section.  This is
+   necessary when compiling PIC code.  */
+#define JUMP_TABLES_IN_TEXT_SECTION
+
+/* Copy this from the svr4 specifications... */
+/* Define the register numbers to be used in Dwarf debugging information.
+   The SVR4 reference port C compiler uses the following register numbers
+   in its Dwarf output code:
+	0 for %eax (gnu regno = 0)
+	1 for %ecx (gnu regno = 2)
+	2 for %edx (gnu regno = 1)
+	3 for %ebx (gnu regno = 3)
+	4 for %esp (gnu regno = 7)
+	5 for %ebp (gnu regno = 6)
+	6 for %esi (gnu regno = 4)
+	7 for %edi (gnu regno = 5)
+   The following three DWARF register numbers are never generated by
+   the SVR4 C compiler or by the GNU compilers, but SDB on x86/svr4
+   believes these numbers have these meanings.
+	8  for %eip    (no gnu equivalent)
+	9  for %eflags (no gnu equivalent)
+	10 for %trapno (no gnu equivalent)
+   It is not at all clear how we should number the FP stack registers
+   for the x86 architecture.  If the version of SDB on x86/svr4 were
+   a bit less brain dead with respect to floating-point then we would
+   have a precedent to follow with respect to DWARF register numbers
+   for x86 FP registers, but the SDB on x86/svr4 is so completely
+   broken with respect to FP registers that it is hardly worth thinking
+   of it as something to strive for compatibility with.
+   The verison of x86/svr4 SDB I have at the moment does (partially)
+   seem to believe that DWARF register number 11 is associated with
+   the x86 register %st(0), but that's about all.  Higher DWARF
+   register numbers don't seem to be associated with anything in
+   particular, and even for DWARF regno 11, SDB only seems to under-
+   stand that it should say that a variable lives in %st(0) (when
+   asked via an `=' command) if we said it was in DWARF regno 11,
+   but SDB still prints garbage when asked for the value of the
+   variable in question (via a `/' command).
+   (Also note that the labels SDB prints for various FP stack regs
+   when doing an `x' command are all wrong.)
+   Note that these problems generally don't affect the native SVR4
+   C compiler because it doesn't allow the use of -O with -g and
+   because when it is *not* optimizing, it allocates a memory
+   location for each floating-point variable, and the memory
+   location is what gets described in the DWARF AT_location
+   attribute for the variable in question.
+   Regardless of the severe mental illness of the x86/svr4 SDB, we
+   do something sensible here and we use the following DWARF
+   register numbers.  Note that these are all stack-top-relative
+   numbers.
+	11 for %st(0) (gnu regno = 8)
+	12 for %st(1) (gnu regno = 9)
+	13 for %st(2) (gnu regno = 10)
+	14 for %st(3) (gnu regno = 11)
+	15 for %st(4) (gnu regno = 12)
+	16 for %st(5) (gnu regno = 13)
+	17 for %st(6) (gnu regno = 14)
+	18 for %st(7) (gnu regno = 15)
+*/
+#undef DBX_REGISTER_NUMBER
+#define DBX_REGISTER_NUMBER(n) \
+((n) == 0 ? 0 \
+ : (n) == 1 ? 2 \
+ : (n) == 2 ? 1 \
+ : (n) == 3 ? 3 \
+ : (n) == 4 ? 6 \
+ : (n) == 5 ? 7 \
+ : (n) == 6 ? 5 \
+ : (n) == 7 ? 4 \
+ : ((n) >= FIRST_STACK_REG && (n) <= LAST_STACK_REG) ? (n)+3 \
+ : (-1))
+
+/* Output assembler code to FILE to increment profiler label # LABELNO
+   for profiling a function entry.  */
+
+#undef FUNCTION_PROFILER
+#define FUNCTION_PROFILER(FILE, LABELNO)  \
+{									\
+  if (flag_pic)								\
+    {									\
+      fprintf (FILE, "\tleal %sP%d@GOTOFF(%%ebx),%%edx\n",		\
+	       LPREFIX, (LABELNO));					\
+      fprintf (FILE, "\tcall *mcount@GOT(%%ebx)\n");			\
+    }									\
+  else									\
+    {									\
+      fprintf (FILE, "\tmovl $%sP%d,%%edx\n", LPREFIX, (LABELNO));	\
+      fprintf (FILE, "\tcall mcount\n");				\
+    }									\
+}
 
 #undef SIZE_TYPE
 #define SIZE_TYPE "unsigned int"
-
+ 
 #undef PTRDIFF_TYPE
 #define PTRDIFF_TYPE "int"
-
+  
 #undef WCHAR_TYPE
 #define WCHAR_TYPE "long int"
-
+   
 #undef WCHAR_TYPE_SIZE
 #define WCHAR_TYPE_SIZE BITS_PER_WORD
+    
+#undef CPP_PREDEFINES
+#define CPP_PREDEFINES "-D__ELF__ -Dunix -Di386 -Dlinux -Asystem(unix) -Asystem(posix) -Acpu(i386) -Amachine(i386)"
 
-#undef HAVE_ATEXIT
-#define HAVE_ATEXIT
-
-/* Linux uses ctype from glibc.a. I am not sure how complete it is.
-   For now, we play safe. It may change later. */
-
-#if 0
-#undef MULTIBYTE_CHARS
-#define MULTIBYTE_CHARS	1
+#undef CPP_SPEC
+#if TARGET_CPU_DEFAULT == 2
+#define CPP_SPEC "%{fPIC:-D__PIC__ -D__pic__} %{fpic:-D__PIC__ -D__pic__} %{!m386:-D__i486__} %{posix:-D_POSIX_SOURCE}"
+#else
+#define CPP_SPEC "%{fPIC:-D__PIC__ -D__pic__} %{fpic:-D__PIC__ -D__pic__} %{m486:-D__i486__} %{posix:-D_POSIX_SOURCE}"
 #endif
 
-#undef LIB_SPEC
+#undef	LIB_SPEC
+#if 1
+/* We no longer link with libc_p.a or libg.a by default. If you
+ * want to profile or debug the Linux C library, please add
+ * -lc_p or -ggdb to LDFLAGS at the link time, respectively.
+ */
+#define LIB_SPEC \
+  "%{!shared: %{mieee-fp:-lieee} %{p:-lgmon} %{pg:-lgmon} \
+     %{!ggdb:-lc} %{ggdb:-lg}}"
+#else
 #define LIB_SPEC \
-"%{mieee-fp:-lieee} %{p*:-lgmon} %{!static:-lc} \
- %{static:%{p*:-lc_p} %{!p:%{!pg:%{!g*:-lc} %{g*:-lg}}}}"
-
-#undef STARTFILE_SPEC
-#define STARTFILE_SPEC  "%{pg:gcrt0.o%s} %{!pg:%{p:gcrt0.o%s} %{!p:crt0.o%s}} %{static:-static}"
-
-
-/* There are conflicting reports about whether this system uses
-   a different assembler syntax.  wilson@cygnus.com says # is right.  */
-#undef COMMENT_BEGIN
-#define COMMENT_BEGIN "#"
-
-#undef ASM_APP_ON
-#define ASM_APP_ON "#APP\n"
-
-#undef ASM_APP_OFF
-#define ASM_APP_OFF "#NO_APP\n"
-
-/* Don't default to pcc-struct-return, because gcc is the only compiler, and
-   we want to retain compatibility with older gcc versions.  */
-#ifndef LINUX_ELF
-#define DEFAULT_PCC_STRUCT_RETURN 0
+  "%{!shared: \
+     %{mieee-fp:-lieee} %{p:-lgmon -lc_p} %{pg:-lgmon -lc_p} \
+       %{!p:%{!pg:%{!g*:-lc} %{g*:-lg}}}}"
 #endif
 
-/* We need that too. */
-#define HANDLE_SYSV_PRAGMA
-
-#undef LINK_SPEC
-
-/* We want to pass -v to linker */
-#if TARGET_CPU_DEFAULT == 2
-#define LINK_SPEC	"%{v:-dll-verbose} %{!m386:-m486}"
+/* Provide a LINK_SPEC appropriate for Linux.  Here we provide support
+   for the special GCC options -static and -shared, which allow us to
+   link things in one of these three modes by applying the appropriate
+   combinations of options at link-time. We like to support here for
+   as many of the other GNU linker options as possible. But I don't
+   have the time to search for those flags. I am sure how to add
+   support for -soname shared_object_name. H.J.
+
+   I took out %{v:%{!V:-V}}. It is too much :-(. They can use
+   -Wl,-V.
+
+   When the -shared link option is used a final link is not being
+   done.  */
+
+/* If ELF is the default format, we should not use /lib/elf. */
+
+#undef	LINK_SPEC
+#ifndef LINUX_DEFAULT_ELF
+#define LINK_SPEC "-m elf_i386 %{shared:-shared} \
+  %{!shared: \
+    %{!ibcs: \
+      %{!static: \
+	%{rdynamic:-export-dynamic} \
+	%{!dynamic-linker:-dynamic-linker /lib/elf/ld-linux.so.1} \
+	%{!rpath:-rpath /lib/elf/}} %{static:-static}}}"
 #else
-#define LINK_SPEC	"%{v:-dll-verbose} %{m486:-m486}"
+#define LINK_SPEC "-m elf_i386 %{shared:-shared} \
+  %{!shared: \
+    %{!ibcs: \
+      %{!static: \
+	%{rdynamic:-export-dynamic} \
+	%{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.1}} \
+	%{static:-static}}}"
 #endif
 
 /* Get perform_* macros to build libgcc.a.  */