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// A contrived example to test the double jump removal peephole.
// RUN: %clang %cflags -O0 %s -o %t.exe
// RUN: llvm-bolt %t.exe -o %t.bolt --peepholes=double-jumps | \
// RUN: FileCheck %s -check-prefix=CHECKBOLT
// RUN: llvm-objdump --no-print-imm-hex -d %t.bolt | FileCheck %s
// CHECKBOLT: BOLT-INFO: Peephole: 1 double jumps patched.
// CHECK: <_Z3foom>:
// CHECK-NEXT: sub sp, sp, #16
// CHECK-NEXT: str x0, [sp, #8]
// CHECK-NEXT: ldr [[REG:x[0-28]+]], [sp, #8]
// CHECK-NEXT: cmp [[REG]], #0
// CHECK-NEXT: b.eq {{.*}} <_Z3foom+0x34>
// CHECK-NEXT: add [[REG]], [[REG]], #1
// CHECK-NEXT: add [[REG]], [[REG]], #1
// CHECK-NEXT: cmp [[REG]], #2
// CHECK-NEXT: b.eq {{.*}} <_Z3foom+0x28>
// CHECK-NEXT: add [[REG]], [[REG]], #1
// CHECK-NEXT: mov [[REG]], x1
// CHECK-NEXT: ldr x1, [sp]
// CHECK-NEXT: b {{.*}} <bar>
// CHECK-NEXT: ldr x1, [sp]
// CHECK-NEXT: add [[REG]], [[REG]], #1
// CHECK-NEXT: b {{.*}} <bar>
extern "C" unsigned long bar(unsigned long count) { return count + 1; }
unsigned long foo(unsigned long count) {
asm volatile(" cmp %0,#0\n"
" b.eq .L7\n"
" add %0, %0, #1\n"
" b .L1\n"
".L1: b .L2\n"
".L2: add %0, %0, #1\n"
" cmp %0, #2\n"
" b.ne .L3\n"
" b .L4\n"
".L3: b .L5\n"
".L5: add %0, %0, #1\n"
".L4: mov %0,x1\n"
" ldr x1, [sp]\n"
" b .L6\n"
".L7: ldr x1, [sp]\n"
" add %0, %0, #1\n"
" b .L6\n"
".L6: b bar\n"
:
: "r"(count)
:);
return count;
}
extern "C" int _start() { return foo(38); }
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