blob: 484779bd6fa88d7b58c57c9b862467b403699702 [file] [log] [blame]
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
; https://bugs.llvm.org/show_bug.cgi?id=37603
; https://reviews.llvm.org/D46760#1123713
; Pattern:
; x >> y << y
; Should be transformed into:
; x & (-1 << y)
; ============================================================================ ;
; Basic positive tests
; ============================================================================ ;
define i32 @positive_samevar(i32 %x, i32 %y) {
; CHECK-LABEL: @positive_samevar(
; CHECK-NEXT: [[TMP1:%.*]] = shl i32 -1, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = and i32 [[TMP1]], [[X:%.*]]
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr i32 %x, %y
%ret = shl i32 %tmp0, %y
ret i32 %ret
}
define i32 @positive_sameconst(i32 %x) {
; CHECK-LABEL: @positive_sameconst(
; CHECK-NEXT: [[TMP1:%.*]] = and i32 [[X:%.*]], -32
; CHECK-NEXT: ret i32 [[TMP1]]
;
%tmp0 = ashr i32 %x, 5
%ret = shl i32 %tmp0, 5
ret i32 %ret
}
define i32 @positive_biggerashr(i32 %x) {
; CHECK-LABEL: @positive_biggerashr(
; CHECK-NEXT: [[TMP0:%.*]] = ashr i32 [[X:%.*]], 10
; CHECK-NEXT: [[RET:%.*]] = shl nsw i32 [[TMP0]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr i32 %x, 10
%ret = shl i32 %tmp0, 5
ret i32 %ret
}
define i32 @positive_biggershl(i32 %x) {
; CHECK-LABEL: @positive_biggershl(
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[X:%.*]], 5
; CHECK-NEXT: [[RET:%.*]] = shl i32 [[TMP1]], 10
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr i32 %x, 5
%ret = shl i32 %tmp0, 10
ret i32 %ret
}
; ============================================================================ ;
; EXACT on the first shift
; ============================================================================ ;
define i32 @positive_samevar_ashrexact(i32 %x, i32 %y) {
; CHECK-LABEL: @positive_samevar_ashrexact(
; CHECK-NEXT: ret i32 [[X:%.*]]
;
%tmp0 = ashr exact i32 %x, %y
%ret = shl i32 %tmp0, %y ; this one is obviously 'nuw'.
ret i32 %ret
}
define i32 @positive_sameconst_ashrexact(i32 %x) {
; CHECK-LABEL: @positive_sameconst_ashrexact(
; CHECK-NEXT: ret i32 [[X:%.*]]
;
%tmp0 = ashr exact i32 %x, 5
%ret = shl i32 %tmp0, 5 ; this one is obviously 'nuw'.
ret i32 %ret
}
define i32 @positive_biggerashr_ashrexact(i32 %x) {
; CHECK-LABEL: @positive_biggerashr_ashrexact(
; CHECK-NEXT: [[RET:%.*]] = ashr exact i32 [[X:%.*]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr exact i32 %x, 10
%ret = shl i32 %tmp0, 5 ; this one is obviously 'nuw'.
ret i32 %ret
}
define i32 @positive_biggershl_ashrexact(i32 %x) {
; CHECK-LABEL: @positive_biggershl_ashrexact(
; CHECK-NEXT: [[RET:%.*]] = shl i32 [[X:%.*]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr exact i32 %x, 5
%ret = shl i32 %tmp0, 10
ret i32 %ret
}
define i32 @positive_biggershl_ashrexact_shlnuw(i32 %x) {
; CHECK-LABEL: @positive_biggershl_ashrexact_shlnuw(
; CHECK-NEXT: [[RET:%.*]] = shl nuw i32 [[X:%.*]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr exact i32 %x, 5
%ret = shl nuw i32 %tmp0, 10
ret i32 %ret
}
; ============================================================================ ;
; Vector
; ============================================================================ ;
define <2 x i32> @positive_samevar_vec(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @positive_samevar_vec(
; CHECK-NEXT: [[TMP1:%.*]] = shl <2 x i32> <i32 -1, i32 -1>, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = and <2 x i32> [[TMP1]], [[X:%.*]]
; CHECK-NEXT: ret <2 x i32> [[RET]]
;
%tmp0 = ashr <2 x i32> %x, %y
%ret = shl <2 x i32> %tmp0, %y
ret <2 x i32> %ret
}
; ============================================================================ ;
; Constant Vectors
; ============================================================================ ;
define <2 x i32> @positive_sameconst_vec(<2 x i32> %x) {
; CHECK-LABEL: @positive_sameconst_vec(
; CHECK-NEXT: [[TMP1:%.*]] = and <2 x i32> [[X:%.*]], <i32 -32, i32 -32>
; CHECK-NEXT: ret <2 x i32> [[TMP1]]
;
%tmp0 = ashr <2 x i32> %x, <i32 5, i32 5>
%ret = shl <2 x i32> %tmp0, <i32 5, i32 5>
ret <2 x i32> %ret
}
define <3 x i32> @positive_sameconst_vec_undef0(<3 x i32> %x) {
; CHECK-LABEL: @positive_sameconst_vec_undef0(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 5, i32 5, i32 5>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 undef, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 5, i32 5>
ret <3 x i32> %ret
}
define <3 x i32> @positive_sameconst_vec_undef1(<3 x i32> %x) {
; CHECK-LABEL: @positive_sameconst_vec_undef1(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 5, i32 5, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 5, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 undef, i32 5>
ret <3 x i32> %ret
}
define <3 x i32> @positive_sameconst_vec_undef2(<3 x i32> %x) {
; CHECK-LABEL: @positive_sameconst_vec_undef2(
; CHECK-NEXT: [[RET:%.*]] = and <3 x i32> [[X:%.*]], <i32 -32, i32 undef, i32 -32>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 undef, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 undef, i32 5>
ret <3 x i32> %ret
}
define <2 x i32> @positive_biggerashr_vec(<2 x i32> %x) {
; CHECK-LABEL: @positive_biggerashr_vec(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <2 x i32> [[X:%.*]], <i32 10, i32 10>
; CHECK-NEXT: [[RET:%.*]] = shl nsw <2 x i32> [[TMP0]], <i32 5, i32 5>
; CHECK-NEXT: ret <2 x i32> [[RET]]
;
%tmp0 = ashr <2 x i32> %x, <i32 10, i32 10>
%ret = shl <2 x i32> %tmp0, <i32 5, i32 5>
ret <2 x i32> %ret
}
define <3 x i32> @positive_biggerashr_vec_undef0(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggerashr_vec_undef0(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 10, i32 undef, i32 10>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 5, i32 5, i32 5>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 10, i32 undef, i32 10>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 5, i32 5>
ret <3 x i32> %ret
}
define <3 x i32> @positive_biggerashr_vec_undef1(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggerashr_vec_undef1(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 10, i32 10, i32 10>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 10, i32 10, i32 10>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 undef, i32 5>
ret <3 x i32> %ret
}
define <3 x i32> @positive_biggerashr_vec_undef2(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggerashr_vec_undef2(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 10, i32 undef, i32 10>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 10, i32 undef, i32 10>
%ret = shl <3 x i32> %tmp0, <i32 5, i32 undef, i32 5>
ret <3 x i32> %ret
}
define <2 x i32> @positive_biggershl_vec(<2 x i32> %x) {
; CHECK-LABEL: @positive_biggershl_vec(
; CHECK-NEXT: [[TMP1:%.*]] = lshr <2 x i32> [[X:%.*]], <i32 5, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <2 x i32> [[TMP1]], <i32 10, i32 10>
; CHECK-NEXT: ret <2 x i32> [[RET]]
;
%tmp0 = ashr <2 x i32> %x, <i32 5, i32 5>
%ret = shl <2 x i32> %tmp0, <i32 10, i32 10>
ret <2 x i32> %ret
}
define <3 x i32> @positive_biggershl_vec_undef0(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggershl_vec_undef0(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 10, i32 10, i32 10>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 undef, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 10, i32 10, i32 10>
ret <3 x i32> %ret
}
define <3 x i32> @positive_biggershl_vec_undef1(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggershl_vec_undef1(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 5, i32 5, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 10, i32 undef, i32 10>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 5, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 10, i32 undef, i32 10>
ret <3 x i32> %ret
}
define <3 x i32> @positive_biggershl_vec_undef2(<3 x i32> %x) {
; CHECK-LABEL: @positive_biggershl_vec_undef2(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <3 x i32> [[X:%.*]], <i32 5, i32 undef, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <3 x i32> [[TMP0]], <i32 10, i32 undef, i32 10>
; CHECK-NEXT: ret <3 x i32> [[RET]]
;
%tmp0 = ashr <3 x i32> %x, <i32 5, i32 undef, i32 5>
%ret = shl <3 x i32> %tmp0, <i32 10, i32 undef, i32 10>
ret <3 x i32> %ret
}
; ============================================================================ ;
; Positive multi-use tests with constant
; ============================================================================ ;
; FIXME: drop 'exact' once it is no longer needed.
define i32 @positive_sameconst_multiuse(i32 %x) {
; CHECK-LABEL: @positive_sameconst_multiuse(
; CHECK-NEXT: [[TMP0:%.*]] = ashr exact i32 [[X:%.*]], 5
; CHECK-NEXT: call void @use32(i32 [[TMP0]])
; CHECK-NEXT: ret i32 [[X]]
;
%tmp0 = ashr exact i32 %x, 5
call void @use32(i32 %tmp0)
%ret = shl i32 %tmp0, 5
ret i32 %ret
}
define i32 @positive_biggerashr_multiuse(i32 %x) {
; CHECK-LABEL: @positive_biggerashr_multiuse(
; CHECK-NEXT: [[TMP0:%.*]] = ashr exact i32 [[X:%.*]], 10
; CHECK-NEXT: call void @use32(i32 [[TMP0]])
; CHECK-NEXT: [[RET:%.*]] = ashr exact i32 [[X]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr exact i32 %x, 10
call void @use32(i32 %tmp0)
%ret = shl i32 %tmp0, 5
ret i32 %ret
}
define i32 @positive_biggershl_multiuse(i32 %x) {
; CHECK-LABEL: @positive_biggershl_multiuse(
; CHECK-NEXT: [[TMP0:%.*]] = ashr exact i32 [[X:%.*]], 5
; CHECK-NEXT: call void @use32(i32 [[TMP0]])
; CHECK-NEXT: [[RET:%.*]] = shl i32 [[X]], 5
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr exact i32 %x, 5
call void @use32(i32 %tmp0)
%ret = shl i32 %tmp0, 10
ret i32 %ret
}
; ============================================================================ ;
; Constant Non-Splat Vectors
; ============================================================================ ;
define <2 x i32> @positive_biggerashr_vec_nonsplat(<2 x i32> %x) {
; CHECK-LABEL: @positive_biggerashr_vec_nonsplat(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <2 x i32> [[X:%.*]], <i32 5, i32 5>
; CHECK-NEXT: [[RET:%.*]] = shl <2 x i32> [[TMP0]], <i32 5, i32 10>
; CHECK-NEXT: ret <2 x i32> [[RET]]
;
%tmp0 = ashr <2 x i32> %x, <i32 5, i32 5>
%ret = shl <2 x i32> %tmp0, <i32 5, i32 10>
ret <2 x i32> %ret
}
define <2 x i32> @positive_biggerLashr_vec_nonsplat(<2 x i32> %x) {
; CHECK-LABEL: @positive_biggerLashr_vec_nonsplat(
; CHECK-NEXT: [[TMP0:%.*]] = ashr <2 x i32> [[X:%.*]], <i32 5, i32 10>
; CHECK-NEXT: [[RET:%.*]] = shl <2 x i32> [[TMP0]], <i32 5, i32 5>
; CHECK-NEXT: ret <2 x i32> [[RET]]
;
%tmp0 = ashr <2 x i32> %x, <i32 5, i32 10>
%ret = shl <2 x i32> %tmp0, <i32 5, i32 5>
ret <2 x i32> %ret
}
; ============================================================================ ;
; Negative tests. Should not be folded.
; ============================================================================ ;
define i32 @negative_twovars(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @negative_twovars(
; CHECK-NEXT: [[TMP0:%.*]] = ashr i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = shl i32 [[TMP0]], [[Z:%.*]]
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr i32 %x, %y
%ret = shl i32 %tmp0, %z ; $z, not %y
ret i32 %ret
}
declare void @use32(i32)
; One use only.
define i32 @negative_oneuse(i32 %x, i32 %y) {
; CHECK-LABEL: @negative_oneuse(
; CHECK-NEXT: [[TMP0:%.*]] = ashr i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: call void @use32(i32 [[TMP0]])
; CHECK-NEXT: [[RET:%.*]] = shl i32 [[TMP0]], [[Y]]
; CHECK-NEXT: ret i32 [[RET]]
;
%tmp0 = ashr i32 %x, %y
call void @use32(i32 %tmp0)
%ret = shl i32 %tmp0, %y
ret i32 %ret
}