llvm-project/llvm/test/CodeGen/X86/zext-demanded.ll

100 lines
2.4 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s
; Various tests for ands that should be implemented with movzx, but aren't due
; demanded bits shortcomings.
; The backend will insert a zext to promote the shift to i32.
define i16 @test1(i16 %x) {
; CHECK-LABEL: test1:
; CHECK: # %bb.0:
; CHECK-NEXT: movzwl %di, %eax
; CHECK-NEXT: shrl %eax
; CHECK-NEXT: # kill: def %ax killed %ax killed %eax
; CHECK-NEXT: retq
%y = lshr i16 %x, 1
ret i16 %y
}
define i32 @test2(i32 %x) {
; CHECK-LABEL: test2:
; CHECK: # %bb.0:
; CHECK-NEXT: movzwl %di, %eax
; CHECK-NEXT: shrl %eax
; CHECK-NEXT: retq
%y = and i32 %x, 65535
%z = lshr i32 %y, 1
ret i32 %z
}
define i32 @test3(i32 %x) {
; CHECK-LABEL: test3:
; CHECK: # %bb.0:
; CHECK-NEXT: movzbl %dil, %eax
; CHECK-NEXT: shrl %eax
; CHECK-NEXT: retq
%y = and i32 %x, 255
%z = lshr i32 %y, 1
ret i32 %z
}
define i16 @test4(i16 %x) {
; CHECK-LABEL: test4:
; CHECK: # %bb.0:
; CHECK-NEXT: movzbl %dil, %eax
; CHECK-NEXT: shrl %eax
; CHECK-NEXT: # kill: def %ax killed %ax killed %eax
; CHECK-NEXT: retq
%y = and i16 %x, 255
%z = lshr i16 %y, 1
ret i16 %z
}
define i16 @test5(i16 %x) {
; CHECK-LABEL: test5:
; CHECK: # %bb.0:
; CHECK-NEXT: movzwl %di, %eax
; CHECK-NEXT: shrl $9, %eax
; CHECK-NEXT: # kill: def %ax killed %ax killed %eax
; CHECK-NEXT: retq
%y = lshr i16 %x, 9
ret i16 %y
}
define i32 @test6(i32 %x) {
; CHECK-LABEL: test6:
; CHECK: # %bb.0:
; CHECK-NEXT: movzwl %di, %eax
; CHECK-NEXT: shrl $9, %eax
; CHECK-NEXT: retq
%y = and i32 %x, 65535
%z = lshr i32 %y, 9
ret i32 %z
}
; TODO: We could turn this and into a zero extend.
define i32 @test7(i32 %x) {
; CHECK-LABEL: test7:
; CHECK: # %bb.0:
; CHECK-NEXT: # kill: def %edi killed %edi def %rdi
; CHECK-NEXT: andl $65534, %edi # imm = 0xFFFE
; CHECK-NEXT: leal 1(%rdi), %eax
; CHECK-NEXT: retq
%y = and i32 %x, 65534
%z = or i32 %y, 1
ret i32 %z
}
; We actually get a movzx on this one, but only because we canonicalize the and
; after the or before SimplifyDemandedBits messes it up.
define i32 @test8(i32 %x) {
; CHECK-LABEL: test8:
; CHECK: # %bb.0:
; CHECK-NEXT: orl $1, %edi
; CHECK-NEXT: movzwl %di, %eax
; CHECK-NEXT: retq
%y = and i32 %x, 65535
%z = or i32 %y, 1
ret i32 %z
}