i386: Allow non-absolute segment values for lcall/ljmp

Allow an unresolved or non-absolute symbol as the segment operand of an
immediate far jump (`ljmp SEG, OFF') or far call (`lcall SEG, OFF').

gas/

2020-10-05  T.K. Chia  <u1049321969@caramail.com>

	PR gas/26694
	* NEWS: Updated for i386 lcall and ljmp change.
	* config/tc-i386.c (output_interseg_jump): Allow non-absolute
	segment operand for immediate lcall and ljmp.
	* testsuite/gas/i386/jump.d,
	* testsuite/gas/i386/jump.s,
	* testsuite/gas/i386/jump16.d,
	* testsuite/gas/i386/jump16.e,
	* testsuite/gas/i386/jump16.s: Add tests for non-absolute
	segment operand for immediate ljmp.

ld/

2020-10-05  T.K. Chia  <u1049321969@caramail.com>

	PR gas/26694
	* testsuite/ld-i386/ljmp.s,
	* testsuite/ld-i386/ljmp1.d,
	* testsuite/ld-i386/ljmp1.s,
	* testsuite/ld-i386/ljmp2.d,
	* testsuite/ld-i386/ljmp2.s,
	* testsuite/ld-x86-64/ljmp1.d,
	* testsuite/ld-x86-64/ljmp2.d: New testcases.
	* testsuite/ld-i386/i386.exp,
	* testsuite/ld-x86-64/x86-64.exp: Run them.

9 files changed, 80 insertions, 0 deletions

diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 164c099..d0b8ed7 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -342,6 +342,8 @@ run_dump_test "call3g"
 run_dump_test "call3h"
 run_dump_test "jmp1"
 run_dump_test "jmp2"
+run_dump_test "ljmp1"
+run_dump_test "ljmp2"
 run_dump_test "load1"
 run_dump_test "load2"
 run_dump_test "load3"
diff --git a/ld/testsuite/ld-i386/ljmp.s b/ld/testsuite/ld-i386/ljmp.s
new file mode 100644
index 0000000..4b27a25
--- /dev/null
+++ b/ld/testsuite/ld-i386/ljmp.s
@@ -0,0 +1,10 @@
+ .global seg1
+ .equiv seg1, 8
+ .global seg2
+ .equiv seg2, 0x18
+	/* Bad IA-16 segment values --- will overflow R_386_16 (and
+	   R_X86_64_16). */
+ .global seg3
+ .equiv seg3, 0x10000
+ .global seg4
+ .equiv seg4, -0x10001
diff --git a/ld/testsuite/ld-i386/ljmp1.d b/ld/testsuite/ld-i386/ljmp1.d
new file mode 100644
index 0000000..9708ad0
--- /dev/null
+++ b/ld/testsuite/ld-i386/ljmp1.d
@@ -0,0 +1,18 @@
+#name: Absolute non-overflowing relocs in ljmp segments
+#as: --32
+#source: ljmp1.s
+#source: ljmp.s
+#ld: -melf_i386 -z noseparate-code
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+0+[a-f0-9]+ <_start>:
+ +[a-f0-9]+:	0f 22 c0             	mov    %eax,%cr0
+ +[a-f0-9]+:	ea ([0-9a-f]{2} ){4}08 00 	ljmp   \$0x8,\$0x[a-f0-9]+
+
+0+[a-f0-9]+ <foo>:
+ +[a-f0-9]+:	66 ea 00 00 18 00    	ljmpw  \$0x18,\$0x0
diff --git a/ld/testsuite/ld-i386/ljmp1.s b/ld/testsuite/ld-i386/ljmp1.s
new file mode 100644
index 0000000..3ae6882
--- /dev/null
+++ b/ld/testsuite/ld-i386/ljmp1.s
@@ -0,0 +1,9 @@
+ .text
+.code32
+ .global _start
+_start:
+	movl	%eax, %cr0
+	ljmp	$seg1, $foo
+foo:
+	ljmpw	$seg2, $0
+ .p2align 4,0x90
diff --git a/ld/testsuite/ld-i386/ljmp2.d b/ld/testsuite/ld-i386/ljmp2.d
new file mode 100644
index 0000000..b599cf9
--- /dev/null
+++ b/ld/testsuite/ld-i386/ljmp2.d
@@ -0,0 +1,7 @@
+#name: ljmp segment value overflow
+#as: --32
+#source: ljmp2.s
+#source: ljmp.s
+#ld: -melf_i386 -z noseparate-code
+#error: .*relocation truncated to fit: R_386_16 .*
+#error: .*relocation truncated to fit: R_386_16 .*
diff --git a/ld/testsuite/ld-i386/ljmp2.s b/ld/testsuite/ld-i386/ljmp2.s
new file mode 100644
index 0000000..f6a4227
--- /dev/null
+++ b/ld/testsuite/ld-i386/ljmp2.s
@@ -0,0 +1,9 @@
+ .text
+.code32
+ .global _start
+_start:
+	movl	%eax, %cr0
+	ljmp	$seg3, $foo
+foo:
+	ljmpw	$seg4, $0
+ .p2align 4,0x90
diff --git a/ld/testsuite/ld-x86-64/ljmp1.d b/ld/testsuite/ld-x86-64/ljmp1.d
new file mode 100644
index 0000000..eb378fb
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/ljmp1.d
@@ -0,0 +1,17 @@
+#name: Absolute non-overflowing relocs in ljmp segments
+#source: ../ld-i386/ljmp1.s
+#source: ../ld-i386/ljmp.s
+#ld: -z noseparate-code
+#objdump: -Mi386 -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+0+[a-f0-9]+ <_start>:
+ +[a-f0-9]+:	0f 22 c0             	mov    %eax,%cr0
+ +[a-f0-9]+:	ea ([0-9a-f]{2} ){4}08 00 	ljmp   \$0x8,\$0x[a-f0-9]+
+
+0+[a-f0-9]+ <foo>:
+ +[a-f0-9]+:	66 ea 00 00 18 00    	ljmpw  \$0x18,\$0x0
diff --git a/ld/testsuite/ld-x86-64/ljmp2.d b/ld/testsuite/ld-x86-64/ljmp2.d
new file mode 100644
index 0000000..b358182
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/ljmp2.d
@@ -0,0 +1,6 @@
+#name: ljmp segment value overflow
+#source: ../ld-i386/ljmp2.s
+#source: ../ld-i386/ljmp.s
+#ld: -z noseparate-code
+#error: .*relocation truncated to fit: R_X86_64_16 .*
+#error: .*relocation truncated to fit: R_X86_64_16 .*
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index 3c0b434..2c2551f 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -519,6 +519,8 @@ run_dump_test "mov2a"
 run_dump_test "mov2b"
 run_dump_test "mov2c"
 run_dump_test "mov2d"
+run_dump_test "ljmp1"
+run_dump_test "ljmp2"
 run_dump_test "load1a"
 run_dump_test "load1b"
 run_dump_test "load1c"