/
logical-right-shift-until-zero.ll
2299 lines (2048 loc) · 115 KB
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logical-right-shift-until-zero.ll
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=loop-idiom -mtriple=x86_64 -mcpu=corei7 < %s -S | FileCheck %s --check-prefixes=CHECK,NOLZCNT
; RUN: opt -passes=loop-idiom -mtriple=x86_64 -mcpu=core-avx2 < %s -S | FileCheck %s --check-prefixes=CHECK,LZCNT
declare void @escape_inner(i8, i8, i8, i1, i8)
declare void @escape_outer(i8, i8, i8, i1, i8)
declare i8 @gen.i8()
; Most basic pattern; Note that iff the shift amount is offset, said offsetting
; must not cause an overflow, but `add nsw` is fine.
define i8 @p0(i8 %val, i8 %start, i8 %extraoffset) {
; NOLZCNT-LABEL: @p0(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @p0(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[TMP0:%.*]] = sub i8 0, [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i8 [[VAL_NUMACTIVEBITS]], [[TMP0]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; `add nuw` is also fine.
define i8 @p1(i8 %val, i8 %start, i8 %extraoffset) {
; NOLZCNT-LABEL: @p1(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = add nuw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @p1(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[TMP0:%.*]] = sub i8 0, [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i8 [[VAL_NUMACTIVEBITS]], [[TMP0]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = add nuw i8 [[IV]], [[EXTRAOFFSET]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nuw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; `sub nsw` is also fine.
define i8 @p2(i8 %val, i8 %start, i8 %extraoffset) {
; NOLZCNT-LABEL: @p2(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = sub nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @p2(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i8 [[VAL_NUMACTIVEBITS]], [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = sub nsw i8 [[IV]], [[EXTRAOFFSET]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = sub nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; But `sub nuw` is not fine..
define i8 @n3(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = sub nuw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = sub nuw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Likewise, plain `sub` is not fine.
define i8 @n4(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = sub i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = sub i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Likewise, plain `add` is not fine.
define i8 @n5(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n5(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Of course, we don't have to have an offset
define i8 @p6(i8 %val, i8 %start) {
; NOLZCNT-LABEL: @p6(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[IV]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[IV]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[IV_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @p6(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nuw nsw i8 [[VAL_NUMACTIVEBITS]], 0
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nuw nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[IV]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[IV]], i8 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[IV_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%val.shifted = lshr i8 %val, %iv
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %iv, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %iv.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
declare void @escape_inner.i7(i7, i7, i7, i1, i7)
declare void @escape_outer.i7(i7, i7, i7, i1, i7)
; Other bitwidths are fine also
define i7 @p7(i7 %val, i7 %start, i7 %extraoffset) {
; NOLZCNT-LABEL: @p7(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i7 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = add nsw i7 [[IV]], [[EXTRAOFFSET:%.*]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i7 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i7 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i7 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner.i7(i7 [[IV]], i7 [[NBITS]], i7 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i7 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i7 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i7 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i7 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i7 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer.i7(i7 [[IV_RES]], i7 [[NBITS_RES]], i7 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i7 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i7 [[IV_RES]]
;
; LZCNT-LABEL: @p7(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i7 @llvm.ctlz.i7(i7 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i7 7, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[TMP0:%.*]] = sub i7 0, [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i7 [[VAL_NUMACTIVEBITS]], [[TMP0]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i7 @llvm.smax.i7(i7 [[VAL_NUMACTIVEBITS_OFFSET]], i7 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i7 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i7 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i7 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i7 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i7 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i7 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = add nsw i7 [[IV]], [[EXTRAOFFSET]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i7 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i7 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner.i7(i7 [[IV]], i7 [[NBITS]], i7 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i7 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i7 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i7 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i7 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i7 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer.i7(i7 [[IV_RES]], i7 [[NBITS_RES]], i7 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i7 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i7 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i7 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i7 %iv, %extraoffset
%val.shifted = lshr i7 %val, %nbits
%val.shifted.iszero = icmp eq i7 %val.shifted, 0
%iv.next = add i7 %iv, 1
call void @escape_inner.i7(i7 %iv, i7 %nbits, i7 %val.shifted, i1 %val.shifted.iszero, i7 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i7 [ %iv, %loop ]
%nbits.res = phi i7 [ %nbits, %loop ]
%val.shifted.res = phi i7 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i7 [ %iv.next, %loop ]
call void @escape_outer.i7(i7 %iv.res, i7 %nbits.res, i7 %val.shifted.res, i1 %val.shifted.iszero.res, i7 %iv.next.res)
ret i7 %iv.res
}
; Step must be 1
define i8 @n8(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n8(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 2
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 2 ; not 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Cmp-br are commutable
define i8 @t9(i8 %val, i8 %start, i8 %extraoffset) {
; NOLZCNT-LABEL: @t9(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISNOTZERO:%.*]] = icmp ne i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISNOTZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISNOTZERO]], label [[LOOP]], label [[END:%.*]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISNOTZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISNOTZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISNOTZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @t9(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[TMP0:%.*]] = sub i8 0, [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i8 [[VAL_NUMACTIVEBITS]], [[TMP0]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[VAL_SHIFTED_ISNOTZERO:%.*]] = xor i1 [[LOOP_IVCHECK]], true
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISNOTZERO]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISNOTZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISNOTZERO]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISNOTZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.isnotzero = icmp ne i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.isnotzero, i8 %iv.next)
br i1 %val.shifted.isnotzero, label %loop, label %end
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.isnotzero.res = phi i1 [ %val.shifted.isnotzero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.isnotzero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; We want to exit once it becomes zero
define i8 @n10(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n10(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISNOTZERO:%.*]] = icmp ne i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISNOTZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISNOTZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISNOTZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISNOTZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISNOTZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.isnotzero = icmp ne i8 %val.shifted, 0 ; not eq
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.isnotzero, i8 %iv.next)
br i1 %val.shifted.isnotzero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.isnotzero.res = phi i1 [ %val.shifted.isnotzero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.isnotzero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Once it compares zero, we want to exit, not exit when it compares non-zero
define i8 @n11(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n11(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[LOOP]], label [[END:%.*]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %loop, label %end ; wrong destinations
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; We must be comparing with 0
define i8 @n12(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n12(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 1
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 1 ; not 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; Loop must have a single block.
define i8 @n13(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n13(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_END:%.*]] ]
; CHECK-NEXT: br label [[LOOP_END]]
; CHECK: loop.end:
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP_END]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP_END]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP_END]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP_END]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP_END]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop.end ]
br label %loop.end
loop.end:
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop.end ]
%nbits.res = phi i8 [ %nbits, %loop.end ]
%val.shifted.res = phi i8 [ %val.shifted, %loop.end ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop.end ]
%iv.next.res = phi i8 [ %iv.next, %loop.end ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; The comparison must have an equality predicate
define i8 @n14(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n14(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = add nsw i8 [[IV]], [[EXTRAOFFSET:%.*]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp ult i8 [[VAL_SHIFTED]], 1
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; CHECK-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; CHECK-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; CHECK-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %iv, %extraoffset
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp ult i8 %val.shifted, 1 ; not `==0`
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; offset computation can be commuted
define i8 @t15(i8 %val, i8 %start, i8 %extraoffset) {
; NOLZCNT-LABEL: @t15(
; NOLZCNT-NEXT: entry:
; NOLZCNT-NEXT: br label [[LOOP:%.*]]
; NOLZCNT: loop:
; NOLZCNT-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[EXTRAOFFSET:%.*]], [[IV]]
; NOLZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; NOLZCNT-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; NOLZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; NOLZCNT-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; NOLZCNT: end:
; NOLZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; NOLZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; NOLZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]
; NOLZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; NOLZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; NOLZCNT-NEXT: ret i8 [[IV_RES]]
;
; LZCNT-LABEL: @t15(
; LZCNT-NEXT: entry:
; LZCNT-NEXT: [[VAL_NUMLEADINGZEROS:%.*]] = call i8 @llvm.ctlz.i8(i8 [[VAL:%.*]], i1 false)
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS:%.*]] = sub nuw nsw i8 8, [[VAL_NUMLEADINGZEROS]]
; LZCNT-NEXT: [[TMP0:%.*]] = sub i8 0, [[EXTRAOFFSET:%.*]]
; LZCNT-NEXT: [[VAL_NUMACTIVEBITS_OFFSET:%.*]] = add nsw i8 [[VAL_NUMACTIVEBITS]], [[TMP0]]
; LZCNT-NEXT: [[IV_FINAL:%.*]] = call i8 @llvm.smax.i8(i8 [[VAL_NUMACTIVEBITS_OFFSET]], i8 [[START:%.*]])
; LZCNT-NEXT: [[LOOP_BACKEDGETAKENCOUNT:%.*]] = sub nsw i8 [[IV_FINAL]], [[START]]
; LZCNT-NEXT: [[LOOP_TRIPCOUNT:%.*]] = add nuw nsw i8 [[LOOP_BACKEDGETAKENCOUNT]], 1
; LZCNT-NEXT: br label [[LOOP:%.*]]
; LZCNT: loop:
; LZCNT-NEXT: [[LOOP_IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_IV_NEXT:%.*]], [[LOOP]] ]
; LZCNT-NEXT: [[LOOP_IV_NEXT]] = add nuw nsw i8 [[LOOP_IV]], 1
; LZCNT-NEXT: [[LOOP_IVCHECK:%.*]] = icmp eq i8 [[LOOP_IV_NEXT]], [[LOOP_TRIPCOUNT]]
; LZCNT-NEXT: [[IV:%.*]] = add nsw i8 [[LOOP_IV]], [[START]]
; LZCNT-NEXT: [[NBITS:%.*]] = add nsw i8 [[EXTRAOFFSET]], [[IV]]
; LZCNT-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL]], [[NBITS]]
; LZCNT-NEXT: [[IV_NEXT:%.*]] = add i8 [[IV]], 1
; LZCNT-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[LOOP_IVCHECK]], i8 [[IV_NEXT]])
; LZCNT-NEXT: br i1 [[LOOP_IVCHECK]], label [[END:%.*]], label [[LOOP]]
; LZCNT: end:
; LZCNT-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV_FINAL]], [[LOOP]] ]
; LZCNT-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; LZCNT-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[LOOP_IVCHECK]], [[LOOP]] ]
; LZCNT-NEXT: [[IV_NEXT_RES:%.*]] = phi i8 [ [[IV_NEXT]], [[LOOP]] ]
; LZCNT-NEXT: call void @escape_outer(i8 [[IV_RES]], i8 [[NBITS_RES]], i8 [[VAL_SHIFTED_RES]], i1 [[VAL_SHIFTED_ISZERO_RES]], i8 [[IV_NEXT_RES]])
; LZCNT-NEXT: ret i8 [[IV_RES]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ %start, %entry ], [ %iv.next, %loop ]
%nbits = add nsw i8 %extraoffset, %iv ; swapped order
%val.shifted = lshr i8 %val, %nbits
%val.shifted.iszero = icmp eq i8 %val.shifted, 0
%iv.next = add i8 %iv, 1
call void @escape_inner(i8 %iv, i8 %nbits, i8 %val.shifted, i1 %val.shifted.iszero, i8 %iv.next)
br i1 %val.shifted.iszero, label %end, label %loop
end:
%iv.res = phi i8 [ %iv, %loop ]
%nbits.res = phi i8 [ %nbits, %loop ]
%val.shifted.res = phi i8 [ %val.shifted, %loop ]
%val.shifted.iszero.res = phi i1 [ %val.shifted.iszero, %loop ]
%iv.next.res = phi i8 [ %iv.next, %loop ]
call void @escape_outer(i8 %iv.res, i8 %nbits.res, i8 %val.shifted.res, i1 %val.shifted.iszero.res, i8 %iv.next.res)
ret i8 %iv.res
}
; But for `sub nsw`, it is not commutable.
define i8 @n16(i8 %val, i8 %start, i8 %extraoffset) {
; CHECK-LABEL: @n16(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS:%.*]] = sub nsw i8 [[EXTRAOFFSET:%.*]], [[IV]]
; CHECK-NEXT: [[VAL_SHIFTED:%.*]] = lshr i8 [[VAL:%.*]], [[NBITS]]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO:%.*]] = icmp eq i8 [[VAL_SHIFTED]], 0
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: call void @escape_inner(i8 [[IV]], i8 [[NBITS]], i8 [[VAL_SHIFTED]], i1 [[VAL_SHIFTED_ISZERO]], i8 [[IV_NEXT]])
; CHECK-NEXT: br i1 [[VAL_SHIFTED_ISZERO]], label [[END:%.*]], label [[LOOP]]
; CHECK: end:
; CHECK-NEXT: [[IV_RES:%.*]] = phi i8 [ [[IV]], [[LOOP]] ]
; CHECK-NEXT: [[NBITS_RES:%.*]] = phi i8 [ [[NBITS]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_RES:%.*]] = phi i8 [ [[VAL_SHIFTED]], [[LOOP]] ]
; CHECK-NEXT: [[VAL_SHIFTED_ISZERO_RES:%.*]] = phi i1 [ [[VAL_SHIFTED_ISZERO]], [[LOOP]] ]