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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "n8:16:32:64"
define i32 @test1(i32 %x) {
; CHECK-LABEL: @test1(
; CHECK-NEXT: [[SEXT:%.*]] = shl i32 %x, 16
; CHECK-NEXT: [[TMP_3:%.*]] = ashr exact i32 [[SEXT]], 16
; CHECK-NEXT: ret i32 [[TMP_3]]
;
%tmp.1 = and i32 %x, 65535
%tmp.2 = xor i32 %tmp.1, -32768
%tmp.3 = add i32 %tmp.2, 32768
ret i32 %tmp.3
}
define i32 @test2(i32 %x) {
; CHECK-LABEL: @test2(
; CHECK-NEXT: [[SEXT:%.*]] = shl i32 %x, 16
; CHECK-NEXT: [[TMP_3:%.*]] = ashr exact i32 [[SEXT]], 16
; CHECK-NEXT: ret i32 [[TMP_3]]
;
%tmp.1 = and i32 %x, 65535
%tmp.2 = xor i32 %tmp.1, 32768
%tmp.3 = add i32 %tmp.2, -32768
ret i32 %tmp.3
}
define i32 @test3(i16 %P) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: [[TMP_5:%.*]] = sext i16 %P to i32
; CHECK-NEXT: ret i32 [[TMP_5]]
;
%tmp.1 = zext i16 %P to i32
%tmp.4 = xor i32 %tmp.1, 32768
%tmp.5 = add i32 %tmp.4, -32768
ret i32 %tmp.5
}
define i32 @test4(i32 %x) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: [[SEXT:%.*]] = shl i32 %x, 24
; CHECK-NEXT: [[TMP_3:%.*]] = ashr exact i32 [[SEXT]], 24
; CHECK-NEXT: ret i32 [[TMP_3]]
;
%tmp.1 = and i32 %x, 255
%tmp.2 = xor i32 %tmp.1, 128
%tmp.3 = add i32 %tmp.2, -128
ret i32 %tmp.3
}
define i32 @test5(i32 %x) {
; CHECK-LABEL: @test5(
; CHECK-NEXT: [[TMP_2:%.*]] = shl i32 %x, 16
; CHECK-NEXT: [[TMP_4:%.*]] = ashr exact i32 [[TMP_2]], 16
; CHECK-NEXT: ret i32 [[TMP_4]]
;
%tmp.2 = shl i32 %x, 16
%tmp.4 = ashr i32 %tmp.2, 16
ret i32 %tmp.4
}
; If the shift amount equals the difference in width of the destination
; and source scalar types:
; ashr (shl (zext X), C), C --> sext X
define i32 @test6(i16 %P) {
; CHECK-LABEL: @test6(
; CHECK-NEXT: [[TMP_5:%.*]] = sext i16 %P to i32
; CHECK-NEXT: ret i32 [[TMP_5]]
;
%tmp.1 = zext i16 %P to i32
%sext1 = shl i32 %tmp.1, 16
%tmp.5 = ashr i32 %sext1, 16
ret i32 %tmp.5
}
; Vectors should get the same fold as above.
define <2 x i32> @test6_splat_vec(<2 x i12> %P) {
; CHECK-LABEL: @test6_splat_vec(
; CHECK-NEXT: [[ASHR:%.*]] = sext <2 x i12> %P to <2 x i32>
; CHECK-NEXT: ret <2 x i32> [[ASHR]]
;
%z = zext <2 x i12> %P to <2 x i32>
%shl = shl <2 x i32> %z, <i32 20, i32 20>
%ashr = ashr <2 x i32> %shl, <i32 20, i32 20>
ret <2 x i32> %ashr
}
define i32 @test7(i32 %x) {
; CHECK-LABEL: @test7(
; CHECK-NEXT: [[SUB:%.*]] = ashr i32 %x, 5
; CHECK-NEXT: ret i32 [[SUB]]
;
%shr = lshr i32 %x, 5
%xor = xor i32 %shr, 67108864
%sub = add i32 %xor, -67108864
ret i32 %sub
}
|