single-inst-bundling.s
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# RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu -mcpu=pentiumpro %s -o - \
# RUN: | llvm-objdump -disassemble -no-show-raw-insn - | FileCheck -check-prefix=CHECK -check-prefix=CHECK-OPT %s
# RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu -mcpu=pentiumpro -mc-relax-all %s -o - \
# RUN: | llvm-objdump -disassemble -no-show-raw-insn - | FileCheck -check-prefix=CHECK -check-prefix=CHECK-RELAX %s
# Test simple NOP insertion for single instructions.
.text
foo:
# Will be bundle-aligning to 16 byte boundaries
.bundle_align_mode 4
pushq %rbp
pushq %r14
pushq %rbx
movl %edi, %ebx
callq bar
movl %eax, %r14d
imull $17, %ebx, %ebp
# This imull is 3 bytes long and should have started at 0xe, so two bytes
# of nop padding are inserted instead and it starts at 0x10
# CHECK: nop
# CHECK-NEXT: 10: imull
movl %ebx, %edi
callq bar
cmpl %r14d, %ebp
# CHECK-RELAX: nopl
jle .L_ELSE
# Due to the padding that's inserted before the addl, the jump target
# becomes farther by one byte.
# CHECK-OPT: jle 5
# CHECK-RELAX: jle 7
addl %ebp, %eax
# CHECK-OPT: nop
# CHECK-OPT-NEXT:20: addl
# CHECK-RELAX: 26: addl
jmp .L_RET
.L_ELSE:
imull %ebx, %eax
.L_RET:
ret
# Just sanity checking that data fills don't drive bundling crazy
.data
.byte 40
.byte 98