llvm/test/CodeGen/X86/tailcall-cgp-dup.ll
Evan Cheng 9c777a4844 Teach CodeGenPrep to look past bitcast when it's duplicating return instruction
into predecessor blocks to enable tail call optimization.

rdar://11958338


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160894 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-27 21:21:26 +00:00

88 lines
2.4 KiB
LLVM

; RUN: llc < %s -mtriple=x86_64-apple-darwin | FileCheck %s
; Teach CGP to dup returns to enable tail call optimization.
; rdar://9147433
define i32 @foo(i32 %x) nounwind ssp {
; CHECK: foo:
entry:
switch i32 %x, label %return [
i32 1, label %sw.bb
i32 2, label %sw.bb1
i32 3, label %sw.bb3
i32 4, label %sw.bb5
i32 5, label %sw.bb7
i32 6, label %sw.bb9
]
sw.bb: ; preds = %entry
; CHECK: jmp _f1
%call = tail call i32 @f1() nounwind
br label %return
sw.bb1: ; preds = %entry
; CHECK: jmp _f2
%call2 = tail call i32 @f2() nounwind
br label %return
sw.bb3: ; preds = %entry
; CHECK: jmp _f3
%call4 = tail call i32 @f3() nounwind
br label %return
sw.bb5: ; preds = %entry
; CHECK: jmp _f4
%call6 = tail call i32 @f4() nounwind
br label %return
sw.bb7: ; preds = %entry
; CHECK: jmp _f5
%call8 = tail call i32 @f5() nounwind
br label %return
sw.bb9: ; preds = %entry
; CHECK: jmp _f6
%call10 = tail call i32 @f6() nounwind
br label %return
return: ; preds = %entry, %sw.bb9, %sw.bb7, %sw.bb5, %sw.bb3, %sw.bb1, %sw.bb
%retval.0 = phi i32 [ %call10, %sw.bb9 ], [ %call8, %sw.bb7 ], [ %call6, %sw.bb5 ], [ %call4, %sw.bb3 ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ], [ 0, %entry ]
ret i32 %retval.0
}
declare i32 @f1()
declare i32 @f2()
declare i32 @f3()
declare i32 @f4()
declare i32 @f5()
declare i32 @f6()
; rdar://11958338
%0 = type opaque
declare i8* @bar(i8*) uwtable optsize noinline ssp
define hidden %0* @thingWithValue(i8* %self) uwtable ssp {
entry:
; CHECK: thingWithValue:
; CHECK: jmp _bar
br i1 undef, label %if.then.i, label %if.else.i
if.then.i: ; preds = %entry
br label %someThingWithValue.exit
if.else.i: ; preds = %entry
%call4.i = tail call i8* @bar(i8* undef) optsize
br label %someThingWithValue.exit
someThingWithValue.exit: ; preds = %if.else.i, %if.then.i
%retval.0.in.i = phi i8* [ undef, %if.then.i ], [ %call4.i, %if.else.i ]
%retval.0.i = bitcast i8* %retval.0.in.i to %0*
ret %0* %retval.0.i
}