a9f9ceb35f
In 16-bit mode, some of the nop patterns used in 32-bit mode can end up
mangling other instructions. For instance, an aligned "movz" instruction
may have the 0x66 and 0x67 prefixes omitted, because the nop that's used
messes things up.
xorl %ebx, %ebx
.p2align 4, 0x90
movzbl (%esi,%ebx), %ecx
Use instead nop patterns we know 16-bit mode can handle.
Differential Revision: https://reviews.llvm.org/D97268
41 lines
1.3 KiB
ArmAsm
41 lines
1.3 KiB
ArmAsm
# RUN: llvm-mc -filetype=obj -triple=i386-unknown-unknown-code16 %s | llvm-objdump --triple=i386-unknown-unknown-code16 -d - | FileCheck %s
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# Ensure that the "movzbl" is aligned such that the prefixes 0x67 0x66 are
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# properly included in the "movz" instruction.
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# CHECK-LABEL: <test>:
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# CHECK: 1c: 8d b4 00 00 leaw (%si), %si
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# CHECK-NEXT: 20: 66 90 nop
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# CHECK-NEXT: 22: 66 89 c7 movl %eax, %edi
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# CHECK-NEXT: 25: 66 31 db xorl %ebx, %ebx
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# CHECK-NEXT: 28: 8d b4 00 00 leaw (%si), %si
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# CHECK-NEXT: 2c: 8d b4 00 00 leaw (%si), %si
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# CHECK-NEXT: 30: 67 66 0f b6 0c 1e movzbl (%esi,%ebx), %ecx
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# CHECK-NEXT: 36: 66 e8 14 00 00 00 calll 0x50 <called>
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# CHECK-NEXT: 3c: 8d 74 00 leaw (%si), %si
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# CHECK-LABEL: <called>:
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# CHECK-NEXT: 50: 90 nop
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# CHECK-NEXT: 51: 66 c3 retl
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.text
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.code16gcc
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.globl test
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.p2align 4, 0x90
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.type test,@function
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test:
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.nops 34
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movl %eax, %edi
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xorl %ebx, %ebx
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.p2align 4, 0x90
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movzbl (%esi,%ebx), %ecx
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calll called
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.nops 3
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retl
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.p2align 4, 0x90
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.type called,@function
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called:
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.nops 1
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retl
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