llvm/test/CodeGen/X86/patchable-function-entry.ll

   1 ; RUN: llc -mtriple=i386 %s -o - | FileCheck --check-prefixes=CHECK,X86 %s
   2 ; RUN: llc -mtriple=x86_64 %s -o - | FileCheck --check-prefixes=CHECK,X64 %s
   3 ; RUN: llc -mtriple=x86_64 -function-sections %s -o - | FileCheck --check-prefixes=CHECK,X64 %s
   4
   5 define void @f0() "patchable-function-entry"="0" {
   6 ; CHECK-LABEL: f0:
   7 ; CHECK-NEXT: .Lfunc_begin0:
   8 ; CHECK-NOT:   nop
   9 ; CHECK:       ret
  10 ; CHECK-NOT:   .section __patchable_function_entries
  11   ret void
  12 }
  13
  14 define void @f1() "patchable-function-entry"="1" {
  15 ; CHECK-LABEL: f1:
  16 ; CHECK-NEXT: .Lfunc_begin1:
  17 ; CHECK:       nop
  18 ; CHECK-NEXT:  ret
  19 ; CHECK:       .section __patchable_function_entries,"awo",@progbits,f1{{$}}
  20 ; X86:          .p2align 2
  21 ; X86-NEXT:     .long .Lfunc_begin1
  22 ; X64:          .p2align 3
  23 ; X64-NEXT:     .quad .Lfunc_begin1
  24   ret void
  25 }
  26
  27 ;; Without -function-sections, f2 is in the same text section as f1.
  28 ;; They share the __patchable_function_entries section.
  29 ;; With -function-sections, f1 and f2 are in different text sections.
  30 ;; Use separate __patchable_function_entries.
  31 define void @f2() "patchable-function-entry"="2" {
  32 ; CHECK-LABEL: f2:
  33 ; CHECK-NEXT: .Lfunc_begin2:
  34 ; X86:          xchgw %ax, %ax
  35 ; X64:          xchgw %ax, %ax
  36 ; CHECK-NEXT:  ret
  37 ; CHECK:       .section __patchable_function_entries,"awo",@progbits,f2{{$}}
  38 ; X86:          .p2align 2
  39 ; X86-NEXT:     .long .Lfunc_begin2
  40 ; X64:          .p2align 3
  41 ; X64-NEXT:     .quad .Lfunc_begin2
  42   ret void
  43 }
  44
  45 $f3 = comdat any
  46 define void @f3() "patchable-function-entry"="3" comdat {
  47 ; CHECK-LABEL: f3:
  48 ; CHECK-NEXT: .Lfunc_begin3:
  49 ; X86:          xchgw %ax, %ax
  50 ; X86-NEXT:     nop
  51 ; X64:          nopl (%rax)
  52 ; CHECK:       ret
  53 ; CHECK:       .section __patchable_function_entries,"awoG",@progbits,f3,f3,comdat{{$}}
  54 ; X86:          .p2align 2
  55 ; X86-NEXT:     .long .Lfunc_begin3
  56 ; X64:          .p2align 3
  57 ; X64-NEXT:     .quad .Lfunc_begin3
  58   ret void
  59 }
  60
  61 $f5 = comdat any
  62 define void @f5() "patchable-function-entry"="5" comdat {
  63 ; CHECK-LABEL: f5:
  64 ; CHECK-NEXT: .Lfunc_begin4:
  65 ; X86-COUNT-2:  xchgw %ax, %ax
  66 ; X86-NEXT:     nop
  67 ; X64:          nopl 8(%rax,%rax)
  68 ; CHECK-NEXT:  ret
  69 ; CHECK:       .section __patchable_function_entries,"awoG",@progbits,f5,f5,comdat{{$}}
  70 ; X86:          .p2align 2
  71 ; X86-NEXT:     .long .Lfunc_begin4
  72 ; X64:          .p2align 3
  73 ; X64-NEXT:     .quad .Lfunc_begin4
  74   ret void
  75 }
  76
  77 ;; -fpatchable-function-entry=3,2
  78 ;; "patchable-function-prefix" emits data before the function entry label.
  79 ;; We emit 1-byte NOPs before the function entry, so that with a partial patch,
  80 ;; the remaining instructions do not need to be modified.
  81 define void @f3_2() "patchable-function-entry"="1" "patchable-function-prefix"="2" {
  82 ; CHECK-LABEL: .type f3_2,@function
  83 ; CHECK-NEXT: .Ltmp0:
  84 ; CHECK-NEXT:  nop
  85 ; CHECK-NEXT:  nop
  86 ; CHECK-NEXT: f3_2: # @f3_2
  87 ; CHECK:      # %bb.0:
  88 ; CHECK-NEXT:  nop
  89 ; CHECK-NEXT:  ret
  90 ;; .size does not include the prefix.
  91 ; CHECK:      .Lfunc_end5:
  92 ; CHECK-NEXT: .size f3_2, .Lfunc_end5-f3_2
  93 ; CHECK:      .section __patchable_function_entries,"awo",@progbits,f3_2{{$}}
  94 ; X86:         .p2align 2
  95 ; X86-NEXT:    .long .Ltmp0
  96 ; X64:         .p2align 3
  97 ; X64-NEXT:    .quad .Ltmp0
  98   %frame = alloca i8, i32 16
  99   ret void
 100 }