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; RUN: llc -verify-machineinstrs -filetype=obj -o - -mtriple=x86_64-apple-macosx < %s | llvm-objdump --no-print-imm-hex --triple=x86_64-apple-macosx -d - | FileCheck %s
; RUN: llc -verify-machineinstrs -mtriple=x86_64-apple-macosx < %s | FileCheck %s --check-prefix=CHECK-ALIGN
; RUN: llc -verify-machineinstrs -show-mc-encoding -mtriple=i386 < %s | FileCheck %s --check-prefixes=32,32CFI,XCHG
; RUN: llc -verify-machineinstrs -show-mc-encoding -mtriple=i386-windows-msvc < %s | FileCheck %s --check-prefixes=32,MOV
; RUN: llc -verify-machineinstrs -show-mc-encoding -mtriple=i386-windows-msvc -mcpu=pentium3 < %s | FileCheck %s --check-prefixes=32,MOV
; RUN: llc -verify-machineinstrs -show-mc-encoding -mtriple=i386-windows-msvc -mcpu=pentium4 < %s | FileCheck %s --check-prefixes=32,XCHG
; RUN: llc -verify-machineinstrs -show-mc-encoding -mtriple=x86_64-windows-msvc < %s | FileCheck %s --check-prefix=64
declare void @callee(ptr)
define void @f0() "patchable-function"="prologue-short-redirect" {
; CHECK-LABEL: _f0{{>?}}:
; CHECK-NEXT: 66 90 nop
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _f0:
; 32: f0:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax # encoding: [0x66,0x90]
; MOV-NEXT: movl %edi, %edi # encoding: [0x8b,0xff]
; 32-NEXT: retl
; 64: f0:
; 64-NEXT: # %bb.0:
; 64-NEXT: xchgw %ax, %ax # encoding: [0x66,0x90]
; 64-NEXT: retq
ret void
}
define void @f1() "patchable-function"="prologue-short-redirect" "frame-pointer"="all" {
; CHECK-LABEL: _f1
; CHECK-NEXT: ff f5 pushq %rbp
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _f1:
; 32: f1:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax # encoding: [0x66,0x90]
; MOV-NEXT: movl %edi, %edi # encoding: [0x8b,0xff]
; 32-NEXT: pushl %ebp
; 64: f1:
; 64-NEXT: .seh_proc f1
; 64-NEXT: # %bb.0:
; 64-NEXT: pushq %rbp
ret void
}
define void @f2() "patchable-function"="prologue-short-redirect" {
; CHECK-LABEL: _f2
; CHECK-NEXT: 48 81 ec a8 00 00 00 subq $168, %rsp
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _f2:
; 32: f2:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax # encoding: [0x66,0x90]
; MOV-NEXT: movl %edi, %edi # encoding: [0x8b,0xff]
; 32-NEXT: pushl %ebp
; 64: f2:
; 64-NEXT: .seh_proc f2
; 64-NEXT: # %bb.0:
; 64-NEXT: subq $200, %rsp
%ptr = alloca i64, i32 20
call void @callee(ptr %ptr)
ret void
}
define void @f3() "patchable-function"="prologue-short-redirect" optsize {
; CHECK-LABEL: _f3
; CHECK-NEXT: 66 90 nop
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _f3:
; 32: f3:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax
; MOV-NEXT: movl %edi, %edi
; 32-NEXT: retl
; 64: f3:
; 64-NEXT: # %bb.0:
; 64-NEXT: xchgw %ax, %ax
; 64-NEXT: retq
ret void
}
; This testcase happens to produce a KILL instruction at the beginning of the
; first basic block. In this case the 2nd instruction should be turned into a
; patchable one.
; CHECK-LABEL: f4{{>?}}:
; CHECK-NEXT: 8b 0c 37 movl (%rdi,%rsi), %ecx
; 32: f4:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax
; MOV-NEXT: movl %edi, %edi
; 32-NEXT: pushl %ebx
; 64: f4:
; 64-NEXT: # %bb.0:
; 64-NOT: xchgw %ax, %ax
define i32 @f4(ptr %arg1, i64 %arg2, i32 %arg3) "patchable-function"="prologue-short-redirect" {
bb:
%tmp10 = getelementptr i8, ptr %arg1, i64 %arg2
%tmp12 = load i32, ptr %tmp10, align 4
fence acquire
%tmp13 = add i32 %tmp12, %arg3
%tmp14 = cmpxchg ptr %tmp10, i32 %tmp12, i32 %tmp13 seq_cst monotonic
%tmp15 = extractvalue { i32, i1 } %tmp14, 1
br i1 %tmp15, label %bb21, label %bb16
bb16:
br label %bb21
bb21:
%tmp22 = phi i32 [ %tmp12, %bb ], [ %arg3, %bb16 ]
ret i32 %tmp22
}
; This testcase produces an empty function (not even a ret on some targets).
; This scenario can happen with undefined behavior.
; Ensure that the "patchable-function" pass supports this case.
; CHECK-LABEL: _emptyfunc
; CHECK-NEXT: 0f 0b ud2
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _emptyfunc:
; 32: emptyfunc:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax
; MOV-NEXT: movl %edi, %edi
; 64: emptyfunc:
; 64-NEXT: # %bb.0:
; 64-NEXT: xchgw %ax, %ax
; From code: int emptyfunc() {}
define i32 @emptyfunc() "patchable-function"="prologue-short-redirect" {
unreachable
}
; Hotpatch feature must ensure no jump within the function goes to the first instruction.
; From code:
; void jmp_to_start(char *b) {
; do {
; } while ((++(*b++)));
; }
; CHECK-ALIGN: .p2align 4, 0x90
; CHECK-ALIGN: _jmp_to_start:
; 32: jmp_to_start:
; 32CFI-NEXT: .cfi_startproc
; 32-NEXT: # %bb.0:
; XCHG-NEXT: xchgw %ax, %ax
; MOV-NEXT: movl %edi, %edi
; 64: jmp_to_start:
; 64-NEXT: # %bb.0:
; 64-NEXT: xchgw %ax, %ax
define dso_local void @jmp_to_start(ptr inreg nocapture noundef %b) "patchable-function"="prologue-short-redirect" {
entry:
br label %do.body
do.body: ; preds = %do.body, %entry
%b.addr.0 = phi ptr [ %b, %entry ], [ %incdec.ptr, %do.body ]
%incdec.ptr = getelementptr inbounds i8, ptr %b.addr.0, i64 1
%0 = load i8, ptr %b.addr.0, align 1
%inc = add i8 %0, 1
store i8 %inc, ptr %b.addr.0, align 1
%tobool.not = icmp eq i8 %inc, 0
br i1 %tobool.not, label %do.end, label %do.body
do.end: ; preds = %do.body
ret void
}
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