llvm/test/CodeGen/Thumb2/thumb2-ifcvt1-tc.ll
Dale Johannesen c66cdf74a9 Enable tail calls on ARM by default, with some
basic tests.

This has been well tested on Darwin but not elsewhere.
It should work provided the linker correctly resolves
  B.W  <label in other function>
which it has not seen before, at least from llvm-based
compilers.  I'm leaving the arm-tail-calls switch in
until I see if there's any problems because of that;
it might need to be disabled for some environments.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106299 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-18 19:00:18 +00:00

87 lines
2.5 KiB
LLVM

; RUN: llc < %s -mtriple=thumbv7-apple-darwin | FileCheck %s
define i32 @t1(i32 %a, i32 %b, i32 %c, i32 %d) nounwind {
; CHECK: t1:
; CHECK: it ne
; CHECK: cmpne
switch i32 %c, label %cond_next [
i32 1, label %cond_true
i32 7, label %cond_true
]
cond_true:
%tmp12 = add i32 %a, 1
%tmp1518 = add i32 %tmp12, %b
ret i32 %tmp1518
cond_next:
%tmp15 = add i32 %b, %a
ret i32 %tmp15
}
; FIXME: Check for # of unconditional branch after adding branch folding post ifcvt.
define i32 @t2(i32 %a, i32 %b) nounwind {
entry:
; CHECK: t2:
; CHECK: ite gt
; CHECK: subgt
; CHECK: suble
%tmp1434 = icmp eq i32 %a, %b ; <i1> [#uses=1]
br i1 %tmp1434, label %bb17, label %bb.outer
bb.outer: ; preds = %cond_false, %entry
%b_addr.021.0.ph = phi i32 [ %b, %entry ], [ %tmp10, %cond_false ] ; <i32> [#uses=5]
%a_addr.026.0.ph = phi i32 [ %a, %entry ], [ %a_addr.026.0, %cond_false ] ; <i32> [#uses=1]
br label %bb
bb: ; preds = %cond_true, %bb.outer
%indvar = phi i32 [ 0, %bb.outer ], [ %indvar.next, %cond_true ] ; <i32> [#uses=2]
%tmp. = sub i32 0, %b_addr.021.0.ph ; <i32> [#uses=1]
%tmp.40 = mul i32 %indvar, %tmp. ; <i32> [#uses=1]
%a_addr.026.0 = add i32 %tmp.40, %a_addr.026.0.ph ; <i32> [#uses=6]
%tmp3 = icmp sgt i32 %a_addr.026.0, %b_addr.021.0.ph ; <i1> [#uses=1]
br i1 %tmp3, label %cond_true, label %cond_false
cond_true: ; preds = %bb
%tmp7 = sub i32 %a_addr.026.0, %b_addr.021.0.ph ; <i32> [#uses=2]
%tmp1437 = icmp eq i32 %tmp7, %b_addr.021.0.ph ; <i1> [#uses=1]
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=1]
br i1 %tmp1437, label %bb17, label %bb
cond_false: ; preds = %bb
%tmp10 = sub i32 %b_addr.021.0.ph, %a_addr.026.0 ; <i32> [#uses=2]
%tmp14 = icmp eq i32 %a_addr.026.0, %tmp10 ; <i1> [#uses=1]
br i1 %tmp14, label %bb17, label %bb.outer
bb17: ; preds = %cond_false, %cond_true, %entry
%a_addr.026.1 = phi i32 [ %a, %entry ], [ %tmp7, %cond_true ], [ %a_addr.026.0, %cond_false ] ; <i32> [#uses=1]
ret i32 %a_addr.026.1
}
@x = external global i32* ; <i32**> [#uses=1]
define void @foo(i32 %a) nounwind {
entry:
%tmp = load i32** @x ; <i32*> [#uses=1]
store i32 %a, i32* %tmp
ret void
}
; Tail call prevents use of ifcvt in this one. Seems like a win though.
define void @t3(i32 %a, i32 %b) nounwind {
entry:
; CHECK: t3:
; CHECK-NOT: it lt
; CHECK-NOT: poplt
; CHECK: b.w _foo @ TAILCALL
%tmp1 = icmp sgt i32 %a, 10 ; <i1> [#uses=1]
br i1 %tmp1, label %cond_true, label %UnifiedReturnBlock
cond_true: ; preds = %entry
tail call void @foo( i32 %b )
ret void
UnifiedReturnBlock: ; preds = %entry
ret void
}