| Reid Kleckner | a580b6e | 2015-01-30 21:03:31 +0000 | [diff] [blame] | 1 | ; RUN: llc -mtriple=x86_64-windows -show-mc-encoding < %s | FileCheck %s |
| 2 | |
| 3 | ; The Win64 ABI wants tail jmps to use a REX_W prefix so it can distinguish |
| 4 | ; in-function jumps from function exiting jumps. |
| 5 | |
| 6 | define void @tail_jmp_reg(i32, i32, void ()* %fptr) { |
| David Blaikie | 23af648 | 2015-04-16 23:24:18 +0000 | [diff] [blame] | 7 | tail call void () %fptr() |
| Reid Kleckner | a580b6e | 2015-01-30 21:03:31 +0000 | [diff] [blame] | 8 | ret void |
| 9 | } |
| 10 | |
| 11 | ; Check that we merge the REX prefixes into 0x49 instead of 0x48, 0x41. |
| 12 | |
| 13 | ; CHECK-LABEL: tail_jmp_reg: |
| 14 | ; CHECK: rex64 jmpq *%r8 |
| 15 | ; CHECK: encoding: [0x49,0xff,0xe0] |
| 16 | |
| 17 | declare void @tail_tgt() |
| 18 | |
| 19 | define void @tail_jmp_imm() { |
| 20 | tail call void @tail_tgt() |
| 21 | ret void |
| 22 | } |
| 23 | |
| 24 | ; CHECK-LABEL: tail_jmp_imm: |
| 25 | ; CHECK: rex64 jmp tail_tgt |
| 26 | |
| 27 | @g_fptr = global void ()* @tail_tgt |
| 28 | |
| 29 | define void @tail_jmp_mem() { |
| David Blaikie | a79ac14 | 2015-02-27 21:17:42 +0000 | [diff] [blame] | 30 | %fptr = load void ()*, void ()** @g_fptr |
| David Blaikie | 23af648 | 2015-04-16 23:24:18 +0000 | [diff] [blame] | 31 | tail call void () %fptr() |
| Reid Kleckner | a580b6e | 2015-01-30 21:03:31 +0000 | [diff] [blame] | 32 | ret void |
| 33 | } |
| 34 | |
| 35 | ; CHECK-LABEL: tail_jmp_mem: |
| 36 | ; CHECK: rex64 jmpq *g_fptr(%rip) |