x86: Disallow instructions with length > 15 bytes

It is a hard error when an instruction length exceeds the limit of 15
bytes:

[hjl@gnu-cfl-3 tmp]$ cat x.s
	.text
	xacquire lock addq $0x11223344, %fs:(,%eax)
[hjl@gnu-cfl-3 tmp]$ gcc -c x.s
x.s: Assembler messages:
x.s:2: Warning: instruction length of 16 bytes exceeds the limit of 15
[hjl@gnu-cfl-3 tmp]$ objdump -dw x.o

x.o:     file format elf64-x86-64

Disassembly of section .text:

0000000000000000 <.text>:
   0:	64 67 f2 f0 48 81 04 05 00 00 00 00 44 33 22 	xacquire lock (bad)
   f:	11                   	.byte 0x11
[hjl@gnu-cfl-3 tmp]$

and

[hjl@gnu-cfl-3 tmp]$ cat z.s
	addq $0xe0, %fs:0, %rdx
[hjl@gnu-cfl-3 tmp]$ as -o z.o z.s
z.s: Assembler messages:
z.s:1: Warning: instruction length of 16 bytes exceeds the limit of 15
[hjl@gnu-cfl-3 tmp]$ objdump -dw z.o

z.o:     file format elf64-x86-64

Disassembly of section .text:

0000000000000000 <.text>:
   0:	64 62 f4 ec 18 81 04 25 00 00 00 00 e0 00 00 	(bad)
	...
[hjl@gnu-cfl-3 pr31323]$

Instructions with length > 15 bytes are always invalid.  It is quite easy
to generate invalid instructions with AVX now.  We should issue an error
when instruction length exceeds the limit of 15 bytes.

	PR gas/31323
	* config/tc-i386.c (output_insn): Issue an error when instruction
	length exceeds the limit of 15 bytes.
	* testsuite/gas/i386/oversized16.l: Updated.
	* testsuite/gas/i386/oversized64.l: Likewise.
	* testsuite/gas/i386/x86-64-apx-inval.l: New file.
	* testsuite/gas/i386/x86-64-apx-inval.s: Likewise.

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 3e1811a092dc25cc4c1a9c8c44b6d02032c9d18e..8f3a1b6f6864840b4e08992ffc70901fa3d1d9ad 100644 (file)
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -11780,8 +11780,8 @@ output_insn (const struct last_insn *last_insn)
        {
          j = encoding_length (insn_start_frag, insn_start_off, frag_more (0));
          if (j > 15)
-           as_warn (_("instruction length of %u bytes exceeds the limit of 15"),
-                    j);
+           as_bad (_("instruction length of %u bytes exceeds the limit of 15"),
+                   j);
          else if (fragP)
            {
              /* NB: Don't add prefix with GOTPC relocation since

diff --git a/gas/testsuite/gas/i386/oversized16.l b/gas/testsuite/gas/i386/oversized16.l
index 3bf7e1d809561296930390574a4af94b76d2d1d3..e0fc7619bdc187347f7b3473a5f75c558f006de3 100644 (file)
--- a/gas/testsuite/gas/i386/oversized16.l
+++ b/gas/testsuite/gas/i386/oversized16.l
@@ -1,9 +1,9 @@
 .*: Assembler messages:
-.*:6: Warning: instruction length.*
-.*:7: Warning: instruction length.*
-.*:8: Warning: instruction length.*
-.*:10: Warning: instruction length.*
-.*:11: Warning: instruction length.*
+.*:6: Error: instruction length.*
+.*:7: Error: instruction length.*
+.*:8: Error: instruction length.*
+.*:10: Error: instruction length.*
+.*:11: Error: instruction length.*
 GAS LISTING .*
 
 
@@ -12,29 +12,29 @@ GAS LISTING .*
 [      ]*3[    ]+\.code16
 [      ]*4[    ]+
 [      ]*5[    ]+long16:
-[      ]*6[    ]+0000 26678FEA[        ]+lwpins        eax, es:\[eax\*8\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*6[    ]+\?\?\?\? 26678FEA[    ]+lwpins        eax, es:\[eax\*8\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*6[    ]+781204C5[     ]*
 [      ]*6[    ]+00000000[     ]*
 [      ]*6[    ]+44332211[     ]*
-[      ]*7[    ]+0010 26678FEA[        ]+lwpval        eax, es:\[eax\*4\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*7[    ]+\?\?\?\? 26678FEA[    ]+lwpval        eax, es:\[eax\*4\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*7[    ]+78120C85[     ]*
 [      ]*7[    ]+00000000[     ]*
 [      ]*7[    ]+44332211[     ]*
-[      ]*8[    ]+0020 26678FEA[        ]+bextr eax, es:\[eax\*2\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*8[    ]+\?\?\?\? 26678FEA[    ]+bextr eax, es:\[eax\*2\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*8[    ]+78100445[     ]*
 [      ]*8[    ]+00000000[     ]*
 [      ]*8[    ]+44332211[     ]*
 [      ]*9[    ]+
-[      ]*10[   ]+0030 266766F2[        ]+xacquire lock add dword ptr es:\[eax\*2\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*10[   ]+\?\?\?\? 266766F2[    ]+xacquire lock add dword ptr es:\[eax\*2\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*10[   ]+F0810445[     ]*
 [      ]*10[   ]+00000000[     ]*
 [      ]*10[   ]+44332211[     ]*
-[      ]*11[   ]+0040 266766F3[        ]+xrelease lock sub dword ptr es:\[eax\*2\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*11[   ]+\?\?\?\? 266766F3[    ]+xrelease lock sub dword ptr es:\[eax\*2\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*11[   ]+F0812C45[     ]*
 [      ]*11[   ]+00000000[     ]*
 [      ]*11[   ]+44332211[     ]*

diff --git a/gas/testsuite/gas/i386/oversized64.l b/gas/testsuite/gas/i386/oversized64.l
index dc63fb5ae7702066ce46bba21bb759bc4039e825..ac32c4d813951a7ea9620fcc9a305ef9e153f940 100644 (file)
--- a/gas/testsuite/gas/i386/oversized64.l
+++ b/gas/testsuite/gas/i386/oversized64.l
@@ -1,9 +1,9 @@
 .*: Assembler messages:
-.*:5: Warning: instruction length.*
-.*:6: Warning: instruction length.*
-.*:7: Warning: instruction length.*
-.*:9: Warning: instruction length.*
-.*:10: Warning: instruction length.*
+.*:5: Error: instruction length.*
+.*:6: Error: instruction length.*
+.*:7: Error: instruction length.*
+.*:9: Error: instruction length.*
+.*:10: Error: instruction length.*
 GAS LISTING .*
 
 
@@ -11,29 +11,29 @@ GAS LISTING .*
 [      ]*2[    ]+\.intel_syntax noprefix
 [      ]*3[    ]+
 [      ]*4[    ]+long64:
-[      ]*5[    ]+0000 64678FEA[        ]+lwpins        rax, fs:\[eax\*8\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*5[    ]+\?\?\?\? 64678FEA[    ]+lwpins        rax, fs:\[eax\*8\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*5[    ]+F81204C5[     ]*
 [      ]*5[    ]+00000000[     ]*
 [      ]*5[    ]+44332211[     ]*
-[      ]*6[    ]+0010 64678FEA[        ]+lwpval        eax, fs:\[eax\*4\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*6[    ]+\?\?\?\? 64678FEA[    ]+lwpval        eax, fs:\[eax\*4\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*6[    ]+78120C85[     ]*
 [      ]*6[    ]+00000000[     ]*
 [      ]*6[    ]+44332211[     ]*
-[      ]*7[    ]+0020 64678FEA[        ]+bextr rax, fs:\[eax\*2\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*7[    ]+\?\?\?\? 64678FEA[    ]+bextr rax, fs:\[eax\*2\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*7[    ]+F8100445[     ]*
 [      ]*7[    ]+00000000[     ]*
 [      ]*7[    ]+44332211[     ]*
 [      ]*8[    ]+
-[      ]*9[    ]+0030 6567F2F0[        ]+xacquire lock add qword ptr gs:\[eax\*8\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*9[    ]+\?\?\?\? 6567F2F0[    ]+xacquire lock add qword ptr gs:\[eax\*8\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*9[    ]+488104C5[     ]*
 [      ]*9[    ]+00000000[     ]*
 [      ]*9[    ]+44332211[     ]*
-[      ]*10[   ]+0040 6567F3F0[        ]+xrelease lock sub qword ptr gs:\[eax\*8\], 0x11223344
-\*\*\*\*  Warning: instruction length of 16 bytes exceeds the limit of 15
+[      ]*10[   ]+\?\?\?\? 6567F3F0[    ]+xrelease lock sub qword ptr gs:\[eax\*8\], 0x11223344
+\*\*\*\*  Error: instruction length of 16 bytes exceeds the limit of 15
 [      ]*10[   ]+48812CC5[     ]*
 [      ]*10[   ]+00000000[     ]*
 [      ]*10[   ]+44332211[     ]*

diff --git a/gas/testsuite/gas/i386/x86-64-apx-inval.l b/gas/testsuite/gas/i386/x86-64-apx-inval.l
new file mode 100644 (file)
index 0000000..6c1a346
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-apx-inval.l
@@ -0,0 +1,3 @@
+.*: Assembler messages:
+.*:3: Error: instruction length of 16 bytes exceeds the limit of 15
+.*:4: Error: instruction length of 16 bytes exceeds the limit of 15

diff --git a/gas/testsuite/gas/i386/x86-64-apx-inval.s b/gas/testsuite/gas/i386/x86-64-apx-inval.s
new file mode 100644 (file)
index 0000000..bb57817
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-apx-inval.s
@@ -0,0 +1,4 @@
+# Check illegal 64bit APX_F instructions
+       .text
+       addq $0xe0, %fs:0, %rdx
+       xorq $0xe0, foo(%eax,%edx), %rdx

diff --git a/gas/testsuite/gas/i386/x86-64.exp b/gas/testsuite/gas/i386/x86-64.exp
index 6932ba97a4d12745a90281ec058776539f5b7672..b77e8c1002974e8583be55c0dda71a7b54b6b350 100644 (file)
--- a/gas/testsuite/gas/i386/x86-64.exp
+++ b/gas/testsuite/gas/i386/x86-64.exp
@@ -371,6 +371,7 @@ run_dump_test "x86-64-avx512f-rcigrne-intel"
 run_dump_test "x86-64-avx512f-rcigrne"
 run_dump_test "x86-64-avx512f-rcigru-intel"
 run_dump_test "x86-64-avx512f-rcigru"
+run_list_test "x86-64-apx-inval"
 run_list_test "x86-64-apx-egpr-inval"
 run_dump_test "x86-64-apx-evex-promoted-bad"
 run_list_test "x86-64-apx-egpr-promote-inval" "-al"