x86_32-optimal_nop.s
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// RUN: llvm-mc -triple i386-apple-darwin9 -mcpu=pentiumpro %s -filetype=obj -o - | llvm-readobj --file-headers -S --sd -r --symbols --macho-segment --macho-dysymtab --macho-indirect-symbols - | FileCheck %s
# 1 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
# nop
# 0x90
.align 1, 0x90
ret
# 2 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
# xchg %ax,%ax
# 0x66, 0x90
.align 2, 0x90
ret
# 3 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
# nopl (%[re]ax)
# 0x0f, 0x1f, 0x00
.align 2, 0x90
ret
# 4 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
# nopl 0(%[re]ax)
# 0x0f, 0x1f, 0x40, 0x00
.align 3, 0x90
ret
# 5 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
# nopl 0(%[re]ax,%[re]ax,1)
# 0x0f, 0x1f, 0x44, 0x00, 0x00
.align 3, 0x90
ret
# 6 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
# nopw 0(%[re]ax,%[re]ax,1)
# 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00
.align 3, 0x90
ret
# 7 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
# nopl 0L(%[re]ax)
# 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00
.align 3, 0x90
ret
# 8 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
ret
ret
ret
ret
# nopl 0L(%[re]ax,%[re]ax,1)
# 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
.align 3, 0x90
ret
# 9 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
ret
ret
ret
# nopw 0L(%[re]ax,%[re]ax,1)
# 0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# 10 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
ret
ret
ret
# nopw %cs:0L(%[re]ax,%[re]ax,1)
# 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# 11 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
ret
# nopw %cs:0L(%[re]ax,%[re]ax,1)
# 0x66, 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# 12 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
ret
# nopw 0(%[re]ax,%[re]ax,1)
# nopw 0(%[re]ax,%[re]ax,1)
# 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
# 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00
.align 4, 0x90
ret
# 13 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
ret
# nopw 0(%[re]ax,%[re]ax,1)
# nopl 0L(%[re]ax)
# 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
# 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# 14 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
ret
# nopl 0L(%[re]ax)
# nopl 0L(%[re]ax)
# 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
# 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# 15 byte nop test
.align 4, 0 # start with 16 byte alignment filled with zeros
ret
# nopl 0L(%[re]ax)
# nopl 0L(%[re]ax,%[re]ax,1)
# 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
# 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
.align 4, 0x90
ret
# Only the .text sections gets optimal nops.
.section __TEXT,__const
f0:
.byte 0
.align 4, 0x90
.long 0
// CHECK: File: <stdin>
// CHECK: Format: Mach-O 32-bit i386
// CHECK: Arch: i386
// CHECK: AddressSize: 32bit
// CHECK: MachHeader {
// CHECK: Magic: Magic (0xFEEDFACE)
// CHECK: CpuType: X86 (0x7)
// CHECK: CpuSubType: CPU_SUBTYPE_I386_ALL (0x3)
// CHECK: FileType: Relocatable (0x1)
// CHECK: NumOfLoadCommands: 4
// CHECK: SizeOfLoadCommands: 312
// CHECK: Flags [ (0x0)
// CHECK: ]
// CHECK: }
// CHECK: Sections [
// CHECK: Section {
// CHECK: Index: 0
// CHECK: Name: __text (5F 5F 74 65 78 74 00 00 00 00 00 00 00 00 00 00)
// CHECK: Segment: __TEXT (5F 5F 54 45 58 54 00 00 00 00 00 00 00 00 00 00)
// CHECK: Address: 0x0
// CHECK: Size: 0x151
// CHECK: Offset: 340
// CHECK: Alignment: 4
// CHECK: RelocationOffset: 0x0
// CHECK: RelocationCount: 0
// CHECK: Type: Regular (0x0)
// CHECK: Attributes [ (0x800004)
// CHECK: PureInstructions (0x800000)
// CHECK: SomeInstructions (0x4)
// CHECK: ]
// CHECK: Reserved1: 0x0
// CHECK: Reserved2: 0x0
// CHECK: SectionData (
// CHECK: 0000: C390C300 00000000 00000000 00000000 |................|
// CHECK: 0010: C3C36690 C3000000 00000000 00000000 |..f.............|
// CHECK: 0020: C30F1F00 C3000000 00000000 00000000 |................|
// CHECK: 0030: C3C3C3C3 0F1F4000 C3000000 00000000 |......@.........|
// CHECK: 0040: C3C3C30F 1F440000 C3000000 00000000 |.....D..........|
// CHECK: 0050: C3C3660F 1F440000 C3000000 00000000 |..f..D..........|
// CHECK: 0060: C30F1F80 00000000 C3000000 00000000 |................|
// CHECK: 0070: C3C3C3C3 C3C3C3C3 C3000000 00000000 |................|
// CHECK: 0080: C3C3C3C3 C3C3C366 0F1F8400 00000000 |.......f........|
// CHECK: 0090: C3000000 00000000 00000000 00000000 |................|
// CHECK: 00A0: C3C3C3C3 C3C3C366 0F1F8400 00000000 |.......f........|
// CHECK: 00B0: C3000000 00000000 00000000 00000000 |................|
// CHECK: 00C0: C3C3C3C3 C3662E0F 1F840000 00000090 |.....f..........|
// CHECK: 00D0: C3000000 00000000 00000000 00000000 |................|
// CHECK: 00E0: C3C3C3C3 662E0F1F 84000000 00006690 |....f.........f.|
// CHECK: 00F0: C3000000 00000000 00000000 00000000 |................|
// CHECK: 0100: C3C3C366 2E0F1F84 00000000 000F1F00 |...f............|
// CHECK: 0110: C3000000 00000000 00000000 00000000 |................|
// CHECK: 0120: C3C3662E 0F1F8400 00000000 0F1F4000 |..f...........@.|
// CHECK: 0130: C3000000 00000000 00000000 00000000 |................|
// CHECK: 0140: C3662E0F 1F840000 0000000F 1F440000 |.f...........D..|
// CHECK: 0150: C3 |.|
// CHECK: )
// CHECK: }
// CHECK: Section {
// CHECK: Index: 1
// CHECK: Name: __const (5F 5F 63 6F 6E 73 74 00 00 00 00 00 00 00 00 00)
// CHECK: Segment: __TEXT (5F 5F 54 45 58 54 00 00 00 00 00 00 00 00 00 00)
// CHECK: Address: 0x160
// CHECK: Size: 0x14
// CHECK: Offset: 692
// CHECK: Alignment: 4
// CHECK: RelocationOffset: 0x0
// CHECK: RelocationCount: 0
// CHECK: Type: Regular (0x0)
// CHECK: Attributes [ (0x0)
// CHECK: ]
// CHECK: Reserved1: 0x0
// CHECK: Reserved2: 0x0
// CHECK: SectionData (
// CHECK: 0000: 00909090 90909090 90909090 90909090 |................|
// CHECK: 0010: 00000000 |....|
// CHECK: )
// CHECK: }
// CHECK: ]
// CHECK: Relocations [
// CHECK: ]
// CHECK: Symbols [
// CHECK: Symbol {
// CHECK: Name: f0 (1)
// CHECK: Type: Section (0xE)
// CHECK: Section: __const (0x2)
// CHECK: RefType: UndefinedNonLazy (0x0)
// CHECK: Flags [ (0x0)
// CHECK: ]
// CHECK: Value: 0x160
// CHECK: }
// CHECK: ]
// CHECK: Indirect Symbols {
// CHECK: Number: 0
// CHECK: Symbols [
// CHECK: ]
// CHECK: }
// CHECK: Segment {
// CHECK: Cmd: LC_SEGMENT
// CHECK: Name:
// CHECK: Size: 192
// CHECK: vmaddr: 0x0
// CHECK: vmsize: 0x174
// CHECK: fileoff: 340
// CHECK: filesize: 372
// CHECK: maxprot: rwx
// CHECK: initprot: rwx
// CHECK: nsects: 2
// CHECK: flags: 0x0
// CHECK: }
// CHECK: Dysymtab {
// CHECK: ilocalsym: 0
// CHECK: nlocalsym: 1
// CHECK: iextdefsym: 1
// CHECK: nextdefsym: 0
// CHECK: iundefsym: 1
// CHECK: nundefsym: 0
// CHECK: tocoff: 0
// CHECK: ntoc: 0
// CHECK: modtaboff: 0
// CHECK: nmodtab: 0
// CHECK: extrefsymoff: 0
// CHECK: nextrefsyms: 0
// CHECK: indirectsymoff: 0
// CHECK: nindirectsyms: 0
// CHECK: extreloff: 0
// CHECK: nextrel: 0
// CHECK: locreloff: 0
// CHECK: nlocrel: 0
// CHECK: }