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1# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=5 -x86-pad-for-align=1 | llvm-objdump --no-print-imm-hex -d - | FileCheck %s2 3# This test file highlights the interactions between prefix padding and4# relaxation padding.5 6 .file "test.c"7 .text8 .section .text9 # We can both relax and prefix for padding purposes, but the moment, we10 # can't prefix without first having relaxed.11 # CHECK: .text12 # CHECK: 0: eb 1f jmp13 # CHECK: 2: eb 1d jmp14 # CHECK: 4: eb 1b jmp15 # CHECK: 6: eb 19 jmp16 # CHECK: 8: eb 17 jmp17 # CHECK: a: 2e 2e 2e 2e 2e e9 0d 00 00 00 jmp18 # CHECK: 14: 2e 2e 2e 2e 2e e9 03 00 00 00 jmp19 # CHECK: 1e: 66 90 nop20 # CHECK: 20: cc int321 .p2align 422 jmp foo23 jmp foo24 jmp foo25 jmp foo26 jmp foo27 jmp foo28 jmp foo29 .p2align 530 int331foo:32 ret33 34 # Canonical toy loop to show benefit - we can align the loop header with35 # fewer nops by relaxing the branch, even though we don't need to36 # CHECK: <loop_preheader>:37 # CHECK: 45: 48 85 c0 testq %rax, %rax38 # CHECK: 48: 2e 2e 2e 2e 0f 8e 1e 00 00 00 jle 0x70 <loop_exit>39 # CHECK: 52: 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 nopw %cs:(%rax,%rax)40 # CHECK: <loop_header>:41 # CHECK: 60: 48 83 e8 01 subq $1, %rax42 # CHECK: 64: 48 85 c0 testq %rax, %rax43 # CHECK: 67: 7e 07 jle 0x70 <loop_exit>44 # CHECK: 69: 2e 2e e9 f0 ff ff ff jmp45 # CHECK: <loop_exit>:46 # CHECK: 70: c3 retq47 .p2align 548 .skip 549loop_preheader:50 testq %rax, %rax51 jle loop_exit52 .p2align 553loop_header:54 subq $1, %rax55 testq %rax, %rax56 jle loop_exit57 jmp loop_header58 .p2align 459loop_exit:60 ret61 62 # Correctness cornercase - can't prefix pad jmp without having relaxed it63 # first as doing so would make the relative offset too large64 # CHECK: fd: cc int365 # CHECK: fe: eb 80 jmp 0x80 <loop_exit+0x10>66 # CHECK: 100: cc int367.p2align 568.L1:69.rept 12670 int371.endr72 jmp .L173.rept 3074 int375.endr76.p2align 577