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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare void @use8(i8)
declare void @use32(i32)
; These would crash if we didn't check for a negative shift.
; https://llvm.org/bugs/show_bug.cgi?id=12967
define void @pr12967() {
; CHECK-LABEL: @pr12967(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: br label [[LOOP]]
;
entry:
br label %loop
loop:
%c = phi i32 [ %shl, %loop ], [ undef, %entry ]
%shr = shl i32 %c, 7
%shl = lshr i32 %shr, -2
br label %loop
}
; https://llvm.org/bugs/show_bug.cgi?id=26760
define void @pr26760() {
; CHECK-LABEL: @pr26760(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: br label [[LOOP]]
;
entry:
br label %loop
loop:
%c = phi i32 [ %shl, %loop ], [ undef, %entry ]
%shr = lshr i32 %c, 7
%shl = shl i32 %shr, -2
br label %loop
}
; Converting the 2 shifts to SHL 6 without the AND is wrong.
; https://llvm.org/bugs/show_bug.cgi?id=8547
define i32 @pr8547(i32* %g) {
; CHECK-LABEL: @pr8547(
; CHECK-NEXT: codeRepl:
; CHECK-NEXT: br label [[FOR_COND:%.*]]
; CHECK: for.cond:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ 0, [[CODEREPL:%.*]] ], [ 5, [[FOR_COND]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], i32* [[G:%.*]], align 4
; CHECK-NEXT: [[TMP0:%.*]] = shl nuw nsw i32 [[STOREMERGE]], 6
; CHECK-NEXT: [[CONV2:%.*]] = and i32 [[TMP0]], 64
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i32 [[CONV2]], 0
; CHECK-NEXT: br i1 [[TOBOOL]], label [[FOR_COND]], label [[CODEREPL2:%.*]]
; CHECK: codeRepl2:
; CHECK-NEXT: ret i32 [[CONV2]]
;
codeRepl:
br label %for.cond
for.cond:
%storemerge = phi i32 [ 0, %codeRepl ], [ 5, %for.cond ]
store i32 %storemerge, i32* %g, align 4
%shl = shl i32 %storemerge, 30
%conv2 = lshr i32 %shl, 24
%tobool = icmp eq i32 %conv2, 0
br i1 %tobool, label %for.cond, label %codeRepl2
codeRepl2:
ret i32 %conv2
}
; Two same direction shifts that add up to more than the bitwidth should get
; folded to zero.
define i32 @shl_shl(i32 %A) {
; CHECK-LABEL: @shl_shl(
; CHECK-NEXT: ret i32 0
;
%B = shl i32 %A, 6
%C = shl i32 %B, 28
ret i32 %C
}
define <2 x i33> @shl_shl_splat_vec(<2 x i33> %A) {
; CHECK-LABEL: @shl_shl_splat_vec(
; CHECK-NEXT: ret <2 x i33> zeroinitializer
;
%B = shl <2 x i33> %A, <i33 5, i33 5>
%C = shl <2 x i33> %B, <i33 28, i33 28>
ret <2 x i33> %C
}
; FIXME
define <2 x i33> @shl_shl_vec(<2 x i33> %A) {
; CHECK-LABEL: @shl_shl_vec(
; CHECK-NEXT: [[B:%.*]] = shl <2 x i33> [[A:%.*]], <i33 6, i33 5>
; CHECK-NEXT: [[C:%.*]] = shl <2 x i33> [[B]], <i33 27, i33 28>
; CHECK-NEXT: ret <2 x i33> [[C]]
;
%B = shl <2 x i33> %A, <i33 6, i33 5>
%C = shl <2 x i33> %B, <i33 27, i33 28>
ret <2 x i33> %C
}
define i232 @lshr_lshr(i232 %A) {
; CHECK-LABEL: @lshr_lshr(
; CHECK-NEXT: ret i232 0
;
%B = lshr i232 %A, 231
%C = lshr i232 %B, 1
ret i232 %C
}
define <2 x i32> @lshr_lshr_splat_vec(<2 x i32> %A) {
; CHECK-LABEL: @lshr_lshr_splat_vec(
; CHECK-NEXT: ret <2 x i32> zeroinitializer
;
%B = lshr <2 x i32> %A, <i32 28, i32 28>
%C = lshr <2 x i32> %B, <i32 4, i32 4>
ret <2 x i32> %C
}
define <2 x i32> @lshr_lshr_vec(<2 x i32> %A) {
; CHECK-LABEL: @lshr_lshr_vec(
; CHECK-NEXT: ret <2 x i32> zeroinitializer
;
%B = lshr <2 x i32> %A, <i32 29, i32 28>
%C = lshr <2 x i32> %B, <i32 4, i32 5>
ret <2 x i32> %C
}
define i8 @shl_trunc_bigger_lshr(i32 %x) {
; CHECK-LABEL: @shl_trunc_bigger_lshr(
; CHECK-NEXT: [[SH_DIFF:%.*]] = lshr i32 [[X:%.*]], 2
; CHECK-NEXT: [[TR_SH_DIFF:%.*]] = trunc i32 [[SH_DIFF]] to i8
; CHECK-NEXT: [[LT:%.*]] = and i8 [[TR_SH_DIFF]], -8
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 5
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 3
ret i8 %lt
}
define i8 @shl_trunc_smaller_lshr(i32 %x) {
; CHECK-LABEL: @shl_trunc_smaller_lshr(
; CHECK-NEXT: [[X_TR:%.*]] = trunc i32 [[X:%.*]] to i8
; CHECK-NEXT: [[TR_SH_DIFF:%.*]] = shl i8 [[X_TR]], 2
; CHECK-NEXT: [[LT:%.*]] = and i8 [[TR_SH_DIFF]], -32
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 3
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 5
ret i8 %lt
}
define i24 @shl_trunc_bigger_ashr(i32 %x) {
; CHECK-LABEL: @shl_trunc_bigger_ashr(
; CHECK-NEXT: [[SH_DIFF:%.*]] = ashr i32 [[X:%.*]], 9
; CHECK-NEXT: [[TR_SH_DIFF:%.*]] = trunc i32 [[SH_DIFF]] to i24
; CHECK-NEXT: [[LT:%.*]] = and i24 [[TR_SH_DIFF]], -8
; CHECK-NEXT: ret i24 [[LT]]
;
%rt = ashr i32 %x, 12
%tr = trunc i32 %rt to i24
%lt = shl i24 %tr, 3
ret i24 %lt
}
define i24 @shl_trunc_smaller_ashr(i32 %x) {
; CHECK-LABEL: @shl_trunc_smaller_ashr(
; CHECK-NEXT: [[X_TR:%.*]] = trunc i32 [[X:%.*]] to i24
; CHECK-NEXT: [[TR_SH_DIFF:%.*]] = shl i24 [[X_TR]], 3
; CHECK-NEXT: [[LT:%.*]] = and i24 [[TR_SH_DIFF]], -8192
; CHECK-NEXT: ret i24 [[LT]]
;
%rt = ashr i32 %x, 10
%tr = trunc i32 %rt to i24
%lt = shl i24 %tr, 13
ret i24 %lt
}
define i8 @shl_trunc_bigger_shl(i32 %x) {
; CHECK-LABEL: @shl_trunc_bigger_shl(
; CHECK-NEXT: [[X_TR:%.*]] = trunc i32 [[X:%.*]] to i8
; CHECK-NEXT: [[TR:%.*]] = shl i8 [[X_TR]], 6
; CHECK-NEXT: ret i8 [[TR]]
;
%rt = shl i32 %x, 4
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 2
ret i8 %lt
}
define i8 @shl_trunc_smaller_shl(i32 %x) {
; CHECK-LABEL: @shl_trunc_smaller_shl(
; CHECK-NEXT: [[X_TR:%.*]] = trunc i32 [[X:%.*]] to i8
; CHECK-NEXT: [[TR:%.*]] = shl i8 [[X_TR]], 6
; CHECK-NEXT: ret i8 [[TR]]
;
%rt = shl i32 %x, 2
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 4
ret i8 %lt
}
define i8 @shl_trunc_bigger_lshr_use1(i32 %x) {
; CHECK-LABEL: @shl_trunc_bigger_lshr_use1(
; CHECK-NEXT: [[RT:%.*]] = lshr i32 [[X:%.*]], 5
; CHECK-NEXT: call void @use32(i32 [[RT]])
; CHECK-NEXT: [[TR:%.*]] = trunc i32 [[RT]] to i8
; CHECK-NEXT: [[LT:%.*]] = shl i8 [[TR]], 3
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 5
call void @use32(i32 %rt)
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 3
ret i8 %lt
}
define i8 @shl_trunc_smaller_lshr_use1(i32 %x) {
; CHECK-LABEL: @shl_trunc_smaller_lshr_use1(
; CHECK-NEXT: [[RT:%.*]] = lshr i32 [[X:%.*]], 3
; CHECK-NEXT: call void @use32(i32 [[RT]])
; CHECK-NEXT: [[TR:%.*]] = trunc i32 [[RT]] to i8
; CHECK-NEXT: [[LT:%.*]] = shl i8 [[TR]], 5
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 3
call void @use32(i32 %rt)
%tr = trunc i32 %rt to i8
%lt = shl i8 %tr, 5
ret i8 %lt
}
define i8 @shl_trunc_bigger_lshr_use2(i32 %x) {
; CHECK-LABEL: @shl_trunc_bigger_lshr_use2(
; CHECK-NEXT: [[RT:%.*]] = lshr i32 [[X:%.*]], 5
; CHECK-NEXT: [[TR:%.*]] = trunc i32 [[RT]] to i8
; CHECK-NEXT: call void @use8(i8 [[TR]])
; CHECK-NEXT: [[LT:%.*]] = shl i8 [[TR]], 3
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 5
%tr = trunc i32 %rt to i8
call void @use8(i8 %tr)
%lt = shl i8 %tr, 3
ret i8 %lt
}
define i8 @shl_trunc_smaller_lshr_use2(i32 %x) {
; CHECK-LABEL: @shl_trunc_smaller_lshr_use2(
; CHECK-NEXT: [[RT:%.*]] = lshr i32 [[X:%.*]], 3
; CHECK-NEXT: [[TR:%.*]] = trunc i32 [[RT]] to i8
; CHECK-NEXT: call void @use8(i8 [[TR]])
; CHECK-NEXT: [[LT:%.*]] = shl i8 [[TR]], 5
; CHECK-NEXT: ret i8 [[LT]]
;
%rt = lshr i32 %x, 3
%tr = trunc i32 %rt to i8
call void @use8(i8 %tr)
%lt = shl i8 %tr, 5
ret i8 %lt
}
|
