; RUN: llc -mtriple=x86_64-- -O2 -start-after=stack-protector -stop-before=loops %s -o - | FileCheck %s

; This test verifies the fix for PR33368.
;
; The expected outcome of the operation is to store bytes 0 and 2 of the incoming
; parameter into c2 (a 2 x i8 vector). DAGCombine converts shuffles into a
; sequence of extend and subsequent truncate operations. The bug was that an extension
; by 4 followed by a truncation by 8 was completely eliminated.

; The test checks for the correct sequence of operations that results from the
; preservation of the extend/truncate operations mentioned above (2 extend and
; 3 truncate instructions).
;
; NOTE: This operation could be collapsed in to a single truncate. Once that is done
; this test will have to be adjusted.

; CHECK:      PUNPCKLBWrr
; CHECK:      PUNPCKLWDrr
; CHECK:      PACKUSWBrr
; CHECK:      PACKUSWBrr
; CHECK:      PACKUSWBrr

define void @test(double %vec.coerce) local_unnamed_addr {
entry:
  %c2 = alloca <2 x i8>, align 2
  %0 = bitcast double %vec.coerce to <8 x i8>
  %1 = shufflevector <8 x i8> %0, <8 x i8> undef, <4 x i32> <i32 2, i32 undef, i32 undef, i32 0>
  %2 = shufflevector <4 x i8> %1, <4 x i8> undef, <2 x i32> <i32 3, i32 0>
  store volatile <2 x i8> %2, <2 x i8>* %c2, align 2
  br label %if.end

if.end:
  %3 = bitcast <2 x i8> %2 to i16
  ret void
}
