Fix overflow checking for 32-bit pc-relative relocations on x32.

The problem here is that x32 is really using 64-bit addressing,
while pretending to be 32-bit. Even though the object file format
is 32-bit, we need to do the overflow checking with 64-bit
arithmetic (because that's what the hardware will be using).
This patch overrides the pcrela32_check functions in reloc.h
with target-specific versions that do 64-bit checking.

I've also updated the test case to use -Tdata instead of adding
a huge .space directive, to reduce the size of the .o files.

gold/
	PR gold/19567
	* reloc.h (Relocate_functions::Overflow_check): Add comments.
	* x86_64.cc (X86_64_relocate_functions): New class.
	(Target_x86_64::Relocate::relocate): Use the new class.
	* testsuite/Makefile.am (x86_64_overflow_pc32): Add -Tdata option.
	(x32_overflow_pc32): New test case.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/x32_overflow_pc32.sh: New script.
	* testsuite/x86_64_overflow_pc32.s: Remove .space directive.

4 files changed, 82 insertions, 8 deletions

diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index 81f3464..ca24205 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -1080,14 +1080,30 @@ MOSTLYCLEANFILES += x86_64_overflow_pc32.err
 x86_64_overflow_pc32.o: x86_64_overflow_pc32.s
 	$(TEST_AS) -o $@ $<
 x86_64_overflow_pc32.err: x86_64_overflow_pc32.o gcctestdir/ld
-	@echo $(CXXLINK) -Bgcctestdir/ -shared -o x86_64_overflow_pc32 x86_64_overflow_pc32.o "2>$@"
-	@if $(CXXLINK) -Bgcctestdir/ -shared -o x86_64_overflow_pc32 x86_64_overflow_pc32.o 2>$@; \
+	@echo gcctestdir/ld -e bar -Tdata=0x81000000 -o x86_64_overflow_pc32 x86_64_overflow_pc32.o "2>$@"
+	@if gcctestdir/ld -e bar -Tdata=0x81000000 -o x86_64_overflow_pc32 x86_64_overflow_pc32.o 2>$@; \
 	then \
 	  echo 1>&2 "Link of x86_64_overflow_pc32 should have failed"; \
 	  rm -f $@; \
 	  exit 1; \
 	fi
 
+check_SCRIPTS += x32_overflow_pc32.sh
+check_DATA += x32_overflow_pc32.err
+MOSTLYCLEANFILES += x32_overflow_pc32.err
+x86_64_overflow_pc32.o: x86_64_overflow_pc32.s
+	$(TEST_AS) -o $@ $<
+x32_overflow_pc32.o: x86_64_overflow_pc32.s
+	$(TEST_AS) --x32 -o $@ $<
+x32_overflow_pc32.err: x32_overflow_pc32.o gcctestdir/ld
+	@echo gcctestdir/ld -e bar -Tdata=0x81000000 -o x32_overflow_pc32 x32_overflow_pc32.o "2>$@"
+	@if gcctestdir/ld -e bar -Tdata=0x81000000 -o x32_overflow_pc32 x32_overflow_pc32.o 2>$@; \
+	then \
+	  echo 1>&2 "Link of x32_overflow_pc32 should have failed"; \
+	  rm -f $@; \
+	  exit 1; \
+	fi
+
 endif DEFAULT_TARGET_X86_64
 
 if DEFAULT_TARGET_I386
diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index 49f3683..253493f 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -200,7 +200,8 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @GCC_TRUE@@HAVE_STATIC_TRUE@@NATIVE_LINKER_TRUE@@STATIC_TLS_TRUE@@TLS_TRUE@	tls_static_pic_test
 @FN_PTRS_IN_SO_WITHOUT_PIC_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@@TLS_TRUE@am__append_25 = tls_shared_nonpic_test
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_26 = x86_64_mov_to_lea.sh \
-@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.sh
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.sh \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x32_overflow_pc32.sh
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_27 = x86_64_mov_to_lea1.stdout \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea2.stdout \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea3.stdout \
@@ -215,7 +216,8 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea12.stdout \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea13.stdout \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea14.stdout \
-@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.err
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.err \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x32_overflow_pc32.err
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_28 = x86_64_mov_to_lea1 \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea2 \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea3 \
@@ -230,7 +232,8 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea12 \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea13 \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_mov_to_lea14 \
-@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.err
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x86_64_overflow_pc32.err \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	x32_overflow_pc32.err
 @DEFAULT_TARGET_I386_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_29 = i386_mov_to_lea.sh
 @DEFAULT_TARGET_I386_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_30 = i386_mov_to_lea1.stdout  i386_mov_to_lea2.stdout \
 @DEFAULT_TARGET_I386_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	i386_mov_to_lea3.stdout  i386_mov_to_lea4.stdout \
@@ -4445,6 +4448,8 @@ x86_64_mov_to_lea.sh.log: x86_64_mov_to_lea.sh
 	@p='x86_64_mov_to_lea.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 x86_64_overflow_pc32.sh.log: x86_64_overflow_pc32.sh
 	@p='x86_64_overflow_pc32.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
+x32_overflow_pc32.sh.log: x32_overflow_pc32.sh
+	@p='x32_overflow_pc32.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 i386_mov_to_lea.sh.log: i386_mov_to_lea.sh
 	@p='i386_mov_to_lea.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 debug_msg.sh.log: debug_msg.sh
@@ -5491,13 +5496,25 @@ uninstall-am:
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@x86_64_overflow_pc32.o: x86_64_overflow_pc32.s
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_AS) -o $@ $<
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@x86_64_overflow_pc32.err: x86_64_overflow_pc32.o gcctestdir/ld
-@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@echo $(CXXLINK) -Bgcctestdir/ -shared -o x86_64_overflow_pc32 x86_64_overflow_pc32.o "2>$@"
-@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@if $(CXXLINK) -Bgcctestdir/ -shared -o x86_64_overflow_pc32 x86_64_overflow_pc32.o 2>$@; \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@echo gcctestdir/ld -e bar -Tdata=0x81000000 -o x86_64_overflow_pc32 x86_64_overflow_pc32.o "2>$@"
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@if gcctestdir/ld -e bar -Tdata=0x81000000 -o x86_64_overflow_pc32 x86_64_overflow_pc32.o 2>$@; \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	then \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  echo 1>&2 "Link of x86_64_overflow_pc32 should have failed"; \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  rm -f $@; \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  exit 1; \
 @DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	fi
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@x86_64_overflow_pc32.o: x86_64_overflow_pc32.s
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_AS) -o $@ $<
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@x32_overflow_pc32.o: x86_64_overflow_pc32.s
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_AS) --x32 -o $@ $<
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@x32_overflow_pc32.err: x32_overflow_pc32.o gcctestdir/ld
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@echo gcctestdir/ld -e bar -Tdata=0x81000000 -o x32_overflow_pc32 x32_overflow_pc32.o "2>$@"
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	@if gcctestdir/ld -e bar -Tdata=0x81000000 -o x32_overflow_pc32 x32_overflow_pc32.o 2>$@; \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	then \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  echo 1>&2 "Link of x32_overflow_pc32 should have failed"; \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  rm -f $@; \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	  exit 1; \
+@DEFAULT_TARGET_X86_64_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	fi
 
 @DEFAULT_TARGET_I386_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@i386_mov_to_lea1.o: i386_mov_to_lea1.s
 @DEFAULT_TARGET_I386_TRUE@@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_AS) --32 -o $@ $<
diff --git a/gold/testsuite/x32_overflow_pc32.sh b/gold/testsuite/x32_overflow_pc32.sh
new file mode 100755
index 0000000..3a5bcba
--- /dev/null
+++ b/gold/testsuite/x32_overflow_pc32.sh
@@ -0,0 +1,42 @@
+#!/bin/sh
+
+# x86_64_overflow_pc32.sh -- a test case for overflow checking.
+
+# Copyright (C) 2016 Free Software Foundation, Inc.
+# Written by Cary Coutant <ccoutant@gmail.com>.
+
+# This file is part of gold.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+
+check()
+{
+    if ! grep -q "$2" "$1"
+    then
+	echo "Did not find expected error in $1:"
+	echo "   $2"
+	echo ""
+	echo "Actual error output below:"
+	cat "$1"
+	exit 1
+    fi
+}
+
+# We don't know how the compiler might order these variables, so we
+# can't test for the actual offset from .data, hence the regexp.
+check x86_64_overflow_pc32.err "function bar: error: relocation overflow"
+
+exit 0
diff --git a/gold/testsuite/x86_64_overflow_pc32.s b/gold/testsuite/x86_64_overflow_pc32.s
index 7494c53..85d9e82 100644
--- a/gold/testsuite/x86_64_overflow_pc32.s
+++ b/gold/testsuite/x86_64_overflow_pc32.s
@@ -1,5 +1,4 @@
 	.data
-	.space 0x8ff00000
 	.hidden foo
 	.globl	foo
 foo: