| ; RUN: llc -mtriple=x86_64-windows -show-mc-encoding < %s | FileCheck %s |
| |
| ; The Win64 ABI wants tail jmps to use a REX_W prefix so it can distinguish |
| ; in-function jumps from function exiting jumps. |
| |
| define void @tail_jmp_reg(i32, i32, void ()* %fptr) { |
| tail call void () %fptr() |
| ret void |
| } |
| |
| ; Check that we merge the REX prefixes into 0x49 instead of 0x48, 0x41. |
| |
| ; CHECK-LABEL: tail_jmp_reg: |
| ; CHECK: rex64 jmpq *%r8 |
| ; CHECK: encoding: [0x49,0xff,0xe0] |
| |
| declare void @tail_tgt() |
| |
| define void @tail_jmp_imm() { |
| tail call void @tail_tgt() |
| ret void |
| } |
| |
| ; CHECK-LABEL: tail_jmp_imm: |
| ; CHECK: jmp tail_tgt |
| |
| @g_fptr = global void ()* @tail_tgt |
| |
| define void @tail_jmp_mem() { |
| %fptr = load void ()*, void ()** @g_fptr |
| tail call void () %fptr() |
| ret void |
| } |
| |
| ; CHECK-LABEL: tail_jmp_mem: |
| ; CHECK: rex64 jmpq *g_fptr(%rip) |
