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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -O2 -mtriple=x86_64-unknown-unknown | FileCheck %s
; Checks that a zeroing mov is inserted for the trunc/zext pair even when
; the source of the zext is an AssertZext node
; PR28540
define i64 @foo() {
; CHECK-LABEL: foo:
; CHECK: # BB#0:
; CHECK-NEXT: movq $-1, %rax
; CHECK-NEXT: retq
ret i64 -1
}
define i64 @main() {
; CHECK-LABEL: main:
; CHECK: # BB#0:
; CHECK-NEXT: pushq %rax
; CHECK-NEXT: .cfi_def_cfa_offset 16
; CHECK-NEXT: callq foo
; CHECK-NEXT: movabsq $-4294967041, %rcx # imm = 0xFFFFFFFF000000FF
; CHECK-NEXT: andq %rax, %rcx
; CHECK-NEXT: movl %ecx, %ecx
; CHECK-NEXT: leaq (,%rcx,8), %rax
; CHECK-NEXT: subq %rcx, %rax
; CHECK-NEXT: shrq $32, %rax
; CHECK-NEXT: popq %rcx
; CHECK-NEXT: retq
%b = call i64 @foo()
%or = and i64 %b, 18446744069414584575 ; this is 0xffffffff000000ff
%trunc = trunc i64 %or to i32
br label %l
l:
%ext = zext i32 %trunc to i64
%mul = mul i64 %ext, 7
br label %m
m: ; keeps dag combine from seeing the multiply and the shift together
%shr = lshr i64 %mul, 32
trunc i64 %or to i32 ; keeps the and alive so it doesn't simplify
ret i64 %shr
}
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