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