llvm-6502/test/Transforms/TailCallElim/inf-recursion.ll
Benjamin Kramer 6b7603962a TRE: Just erase dead BBs and tweak the iteration loop not to increment the deleted BB iterator.
Leaving empty blocks around just opens up a can of bugs like PR22704. Deleting
them early also slightly simplifies code.

Thanks to Sanjay for the IR test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230856 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 16:47:27 +00:00

55 lines
1.2 KiB
LLVM

; RUN: opt < %s -tailcallelim -S | FileCheck %s
; Don't turn this into an infinite loop, this is probably the implementation
; of fabs and we expect the codegen to lower fabs.
; CHECK: @fabs(double %f)
; CHECK: call
; CHECK: ret
define double @fabs(double %f) {
entry:
%tmp2 = call double @fabs( double %f ) ; <double> [#uses=1]
ret double %tmp2
}
; Do turn other calls into infinite loops though.
; CHECK-LABEL: define double @foo(
; CHECK-NOT: call
; CHECK: }
define double @foo(double %f) {
%t= call double @foo(double %f)
ret double %t
}
; CHECK-LABEL: define float @fabsf(
; CHECK-NOT: call
; CHECK: }
define float @fabsf(float %f) {
%t= call float @fabsf(float 2.0)
ret float %t
}
declare x86_fp80 @fabsl(x86_fp80 %f)
; Don't crash while transforming a function with infinite recursion.
define i32 @PR22704(i1 %bool) {
entry:
br i1 %bool, label %t, label %f
t:
%call1 = call i32 @PR22704(i1 1)
br label %return
f:
%call = call i32 @PR22704(i1 1)
br label %return
return:
ret i32 0
; CHECK-LABEL: @PR22704(
; CHECK: %bool.tr = phi i1 [ %bool, %entry ], [ true, %t ], [ true, %f ]
; CHECK: br i1 %bool.tr, label %t, label %f
}