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| author | Jan Beulich <jbeulich@suse.com> | 2024-10-30 12:12:24 +0100 |
|---|---|---|
| committer | Jan Beulich <jbeulich@suse.com> | 2024-10-30 12:12:24 +0100 |
| commit | d0a9378d985b3fe7b52369ec7c64088f3171fdc9 (patch) | |
| tree | 6cfe81f7024df0242da17aa8ce3642564d5c3e47 | |
| parent | 0a81e17f765a4ae25532810b346545929a721317 (diff) | |
| download | binutils-d0a9378d985b3fe7b52369ec7c64088f3171fdc9.zip binutils-d0a9378d985b3fe7b52369ec7c64088f3171fdc9.tar.gz binutils-d0a9378d985b3fe7b52369ec7c64088f3171fdc9.tar.bz2 | |
x86/APX: squash REX prefix when REX2 is being emitted
We should not (silently) emit a REX prefix ahead of a REX2-encoded insn;
such encodings are illegal. Best we can do is fold the REX bits into the
REX2 prefix, and then zap the REX one from i.prefix[].
| -rw-r--r-- | gas/config/tc-i386.c | 4 | ||||
| -rw-r--r-- | gas/testsuite/gas/i386/x86-64-apx-rex2.d | 4 | ||||
| -rw-r--r-- | gas/testsuite/gas/i386/x86-64-apx-rex2.s | 6 |
3 files changed, 13 insertions, 1 deletions
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 9f68a2f..f6a8c30 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -4527,7 +4527,8 @@ build_rex2_prefix (void) i.vex.bytes[0] = 0xd5; /* For the W R X B bits, the variables of rex prefix will be reused. */ i.vex.bytes[1] = ((i.tm.opcode_space << 7) - | (i.rex2 << 4) | i.rex); + | (i.rex2 << 4) + | ((i.rex | i.prefix[REX_PREFIX]) & 0xf)); } /* Build the EVEX prefix (4-byte) for evex insn @@ -4676,6 +4677,7 @@ static void establish_rex (void) build_rex2_prefix (); /* The individual REX.RXBW bits got consumed. */ i.rex &= REX_OPCODE; + i.prefix[REX_PREFIX] = 0; } else if (i.rex != 0) add_prefix (REX_OPCODE | i.rex); diff --git a/gas/testsuite/gas/i386/x86-64-apx-rex2.d b/gas/testsuite/gas/i386/x86-64-apx-rex2.d index e3cd534..0783f9b 100644 --- a/gas/testsuite/gas/i386/x86-64-apx-rex2.d +++ b/gas/testsuite/gas/i386/x86-64-apx-rex2.d @@ -80,4 +80,8 @@ Disassembly of section .text: [ ]*[a-f0-9]+:[ ]*d5 76 8d 7c 20 01 lea 0x1\(%r16,%r28,1\),%r31d [ ]*[a-f0-9]+:[ ]*d5 12 8d 84 04 81 00 00 00 lea 0x81\(%r20,%r8,1\),%eax [ ]*[a-f0-9]+:[ ]*d5 57 8d bc 04 81 00 00 00 lea 0x81\(%r28,%r8,1\),%r31d +[ ]*[a-f0-9]+:[ ]*d5 14 f7 14 24 \{rex2 0x14\} notl \(%r20\) +[ ]*[a-f0-9]+:[ ]*d5 12 f7 14 24 notl \(%r20,%r12,1\) +[ ]*[a-f0-9]+:[ ]*d5 11 f7 14 24 notl \(%r28\) +[ ]*[a-f0-9]+:[ ]*d5 18 f7 14 24 notq \(%r20\) #pass diff --git a/gas/testsuite/gas/i386/x86-64-apx-rex2.s b/gas/testsuite/gas/i386/x86-64-apx-rex2.s index eaaaaa7..5102dc3 100644 --- a/gas/testsuite/gas/i386/x86-64-apx-rex2.s +++ b/gas/testsuite/gas/i386/x86-64-apx-rex2.s @@ -83,3 +83,9 @@ _start: leal 1(%r16, %r28), %r31d leal 129(%r20, %r8), %eax leal 129(%r28, %r8), %r31d + +## explicit REX prefix + rex.r notl (%r20) + rex.x notl (%r20) + rex.b notl (%r20) + rex.w not (%r20) |