190 lines
		
	
	
		
			5.6 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			190 lines
		
	
	
		
			5.6 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: llc -mtriple=i686-unknown-linux-gnu -O1 < %s | FileCheck %s
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| ; RUN: llc -mtriple=i686-unknown-linux-gnu -O0 < %s | FileCheck %s
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| 
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| ; The MSVC family of x86 calling conventions makes tail calls really tricky.
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| ; Tests of all the various combinations should live here.
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| 
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| declare i32 @cdecl_i32()
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| declare void @cdecl_void()
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| 
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| ; Don't allow tail calling these cdecl functions, because we need to clear the
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| ; incoming stack arguments for these argument-clearing conventions.
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| 
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| define x86_thiscallcc void @thiscall_cdecl_notail(i32 %a, i32 %b, i32 %c) {
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|   tail call void @cdecl_void()
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|   ret void
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| }
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| ; CHECK-LABEL: thiscall_cdecl_notail
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| ; CHECK: calll cdecl_void
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| ; CHECK: retl $8
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| 
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| define x86_stdcallcc void @stdcall_cdecl_notail(i32 %a, i32 %b, i32 %c) {
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|   tail call void @cdecl_void()
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|   ret void
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| }
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| ; CHECK-LABEL: stdcall_cdecl_notail
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| ; CHECK: calll cdecl_void
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| ; CHECK: retl $12
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| 
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| define x86_vectorcallcc void @vectorcall_cdecl_notail(i32 inreg %a, i32 inreg %b, i32 %c) {
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|   tail call void @cdecl_void()
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|   ret void
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| }
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| ; CHECK-LABEL: vectorcall_cdecl_notail
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| ; CHECK: calll cdecl_void
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| ; CHECK: retl $4
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| 
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| define x86_fastcallcc void @fastcall_cdecl_notail(i32 inreg %a, i32 inreg %b, i32 %c) {
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|   tail call void @cdecl_void()
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|   ret void
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| }
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| ; CHECK-LABEL: fastcall_cdecl_notail
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| ; CHECK: calll cdecl_void
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| ; CHECK: retl $4
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| 
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| 
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| ; Tail call to/from callee pop functions can work under the right circumstances:
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| 
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| declare x86_thiscallcc void @no_args_method(i8*)
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| declare x86_thiscallcc void @one_arg_method(i8*, i32)
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| declare x86_thiscallcc void @two_args_method(i8*, i32, i32)
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| declare void @ccall_func()
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| declare void @ccall_func1(i32)
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| 
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| define x86_thiscallcc void @thiscall_thiscall_tail(i8* %this) {
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| entry:
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|   tail call x86_thiscallcc void @no_args_method(i8* %this)
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|   ret void
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| }
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| ; CHECK-LABEL: thiscall_thiscall_tail:
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| ; CHECK: jmp no_args_method
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| 
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| define x86_thiscallcc void @thiscall_thiscall_tail2(i8* %this, i32 %a, i32 %b) {
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| entry:
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|   tail call x86_thiscallcc void @two_args_method(i8* %this, i32 %a, i32 %b)
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|   ret void
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| }
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| ; @two_args_method will take care of popping %a and %b from the stack for us.
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| ; CHECK-LABEL: thiscall_thiscall_tail2:
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| ; CHECK: jmp two_args_method
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| 
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| define x86_thiscallcc void @thiscall_thiscall_notail(i8* %this, i32 %a, i32 %b, i32 %x) {
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| entry:
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|   tail call x86_thiscallcc void @two_args_method(i8* %this, i32 %a, i32 %b)
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|   ret void
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| }
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| ; @two_args_method would not pop %x.
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| ; CHECK-LABEL: thiscall_thiscall_notail:
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| ; CHECK: calll two_args_method
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| ; CHECK: retl $12
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| 
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| define x86_thiscallcc void @thiscall_thiscall_notail2(i8* %this, i32 %a) {
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| entry:
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|   tail call x86_thiscallcc void @no_args_method(i8* %this)
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|   ret void
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| }
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| ; @no_args_method would not pop %x for us. Make sure this is checked even
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| ; when there are no arguments to the call.
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| ; CHECK-LABEL: thiscall_thiscall_notail2:
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| ; CHECK: calll no_args_method
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| ; CHECK: retl $4
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| 
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| define void @ccall_thiscall_tail(i8* %x) {
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| entry:
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|   tail call x86_thiscallcc void @no_args_method(i8* %x)
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|   ret void
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| }
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| ; Tail calling from ccall to thiscall works.
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| ; CHECK-LABEL: ccall_thiscall_tail:
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| ; CHECK: jmp no_args_method
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| 
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| define void @ccall_thiscall_notail(i8* %x, i32 %y) {
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| entry:
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|   tail call x86_thiscallcc void @one_arg_method(i8* %x, i32 %y);
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|   ret void
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| }
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| ; @one_arg_method would pop %y off the stack.
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| ; CHECK-LABEL: ccall_thiscall_notail:
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| ; CHECK: calll one_arg_method
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| 
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| define x86_thiscallcc void @thiscall_ccall_tail(i8* %this) {
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| entry:
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|   tail call void @ccall_func()
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|   ret void
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| }
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| ; Tail call from thiscall to ccall works if no arguments need popping.
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| ; CHECK-LABEL: thiscall_ccall_tail:
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| ; CHECK: jmp ccall_func
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| 
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| define x86_thiscallcc void @thiscall_ccall_notail(i8* %this, i32 %x) {
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| entry:
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|   tail call void @ccall_func1(i32 %x)
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|   ret void
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| }
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| ; No tail call: %x needs to be popped.
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| ; CHECK-LABEL: thiscall_ccall_notail:
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| ; CHECK: calll ccall_func1
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| ; CHECK: retl $4
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| 
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| %S = type { i32 (...)** }
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| define x86_thiscallcc void @tailcall_through_pointer(%S* %this, i32 %a) {
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| entry:
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|   %0 = bitcast %S* %this to void (%S*, i32)***
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|   %vtable = load void (%S*, i32)**, void (%S*, i32)*** %0
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|   %1 = load void (%S*, i32)*, void (%S*, i32)** %vtable
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|   tail call x86_thiscallcc void %1(%S* %this, i32 %a)
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|   ret void
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| }
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| ; Tail calling works through function pointers too.
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| ; CHECK-LABEL: tailcall_through_pointer:
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| ; CHECK: jmpl
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| 
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| define x86_stdcallcc void @stdcall_cdecl_tail() {
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|   tail call void @ccall_func()
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|   ret void
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| }
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| ; stdcall to cdecl works if no arguments need popping.
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| ; CHECK-LABEL: stdcall_cdecl_tail
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| ; CHECK: jmp ccall_func
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| 
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| define x86_vectorcallcc void @vectorcall_cdecl_tail(i32 inreg %a, i32 inreg %b) {
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|   tail call void @ccall_func()
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|   ret void
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| }
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| ; vectorcall to cdecl works if no arguments need popping.
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| ; CHECK-LABEL: vectorcall_cdecl_tail
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| ; CHECK: jmp ccall_func
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| 
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| define x86_fastcallcc void @fastcall_cdecl_tail(i32 inreg %a, i32 inreg %b) {
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|   tail call void @ccall_func()
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|   ret void
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| }
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| ; fastcall to cdecl works if no arguments need popping.
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| ; CHECK-LABEL: fastcall_cdecl_tail
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| ; CHECK: jmp ccall_func
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| 
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| define x86_stdcallcc void @stdcall_thiscall_notail(i8* %this, i32 %a, i32 %b) {
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|   tail call x86_thiscallcc void @two_args_method(i8* %this, i32 %a, i32 %b)
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|   ret void
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| }
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| ; two_args_method will not pop %this.
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| ; CHECK-LABEL: stdcall_thiscall_notail
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| ; CHECK: calll two_args_method
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| 
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| define x86_stdcallcc void @stdcall_thiscall_tail(i32 %a, i32 %b) {
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|   tail call x86_thiscallcc void @two_args_method(i8* null, i32 %a, i32 %b)
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|   ret void
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| }
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| ; The callee pop amounts match up.
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| ; CHECK-LABEL: stdcall_thiscall_tail
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| ; CHECK: jmp two_args_method
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| 
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| declare x86_fastcallcc void @fastcall2(i32 inreg %a, i32 inreg %b)
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| define void @cdecl_fastcall_tail(i32 %a, i32 %b) {
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|   tail call x86_fastcallcc void @fastcall2(i32 %a, i32 %b)
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|   ret void
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| }
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| ; fastcall2 won't pop anything.
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| ; CHECK-LABEL: cdecl_fastcall_tail
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| ; CHECK: jmp fastcall2
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