llvm/test/Analysis/ValueTracking/phi-known-nonzero.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=instsimplify < %s -S | FileCheck %s

define i1 @phi_ugt_non_zero(i8 %x) {
; CHECK-LABEL: @phi_ugt_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[X:%.*]], 32
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    ret i1 false
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp ugt i8 %x, 32
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_uge_non_zero(i8 %x) {
; CHECK-LABEL: @phi_uge_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp uge i8 [[X:%.*]], 32
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    ret i1 false
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp uge i8 %x, 32
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_ugt_non_zero_fail(i8 %x) {
; CHECK-LABEL: @phi_ugt_non_zero_fail(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[X:%.*]], 32
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    [[V:%.*]] = phi i8 [ [[X]], [[ENTRY:%.*]] ], [ 0, [[F]] ]
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[V]], 0
; CHECK-NEXT:    ret i1 [[R]]
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp ugt i8 %x, 32
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [0, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_ult_non_zero(i8 %x) {
; CHECK-LABEL: @phi_ult_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[X:%.*]], 123
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    br label [[F]]
; CHECK:       F:
; CHECK-NEXT:    ret i1 false
;
entry:
  %cmp = icmp ult i8 %x, 123
  br i1 %cmp, label %T, label %F
T:
  br label %F
F:
  %v = phi i8 [ %x, %entry], [-1, %T]
  %r = icmp eq i8 %v, 0
  ret i1 %r
}

define i1 @phi_ule_non_zero(i8 %x) {
; CHECK-LABEL: @phi_ule_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i8 [[X:%.*]], 123
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    br label [[F]]
; CHECK:       F:
; CHECK-NEXT:    ret i1 false
;
entry:
  %cmp = icmp ule i8 %x, 123
  br i1 %cmp, label %T, label %F
T:
  br label %F
F:
  %v = phi i8 [ %x, %entry], [-1, %T]
  %r = icmp eq i8 %v, 0
  ret i1 %r
}

define i1 @phi_ule_non_zero_fail_wrong_succ(i8 %x) {
; CHECK-LABEL: @phi_ule_non_zero_fail_wrong_succ(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ule i8 [[X:%.*]], 123
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    [[V:%.*]] = phi i8 [ [[X]], [[ENTRY:%.*]] ], [ -1, [[F]] ]
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[V]], 0
; CHECK-NEXT:    ret i1 [[R]]
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp ule i8 %x, 123
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_ult_non_zero_fail(i8 %x) {
; CHECK-LABEL: @phi_ult_non_zero_fail(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[X:%.*]], 123
; CHECK-NEXT:    [[X2:%.*]] = add i8 [[X]], [[X]]
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    br label [[F]]
; CHECK:       F:
; CHECK-NEXT:    [[V:%.*]] = phi i8 [ [[X2]], [[ENTRY:%.*]] ], [ -1, [[T]] ]
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[V]], 0
; CHECK-NEXT:    ret i1 [[R]]
;
entry:
  %cmp = icmp ult i8 %x, 123
  %x2 = add i8 %x, %x
  br i1 %cmp, label %T, label %F
T:
  br label %F
F:
  %v = phi i8 [ %x2, %entry], [-1, %T]
  %r = icmp eq i8 %v, 0
  ret i1 %r
}

define i1 @phi_ne_non_zero(i8 %x) {
; CHECK-LABEL: @phi_ne_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    ret i1 false
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp ne i8 %x, 0
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_eq_non_zero(i8 %x) {
; CHECK-LABEL: @phi_eq_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[X:%.*]], 44
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    ret i1 false
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp eq i8 %x, 44
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_eq_non_zero2(i8 %x) {
; CHECK-LABEL: @phi_eq_non_zero2(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    br label [[F]]
; CHECK:       F:
; CHECK-NEXT:    ret i1 false
;
entry:
  %cmp = icmp eq i8 %x, 0
  br i1 %cmp, label %T, label %F
T:
  br label %F
F:
  %v = phi i8 [ %x, %entry], [-1, %T]
  %r = icmp eq i8 %v, 0
  ret i1 %r
}

define i1 @phi_sgt_non_zero(i8 %x) {
; CHECK-LABEL: @phi_sgt_non_zero(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[X:%.*]], 1
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    ret i1 false
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp sgt i8 %x, 1
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

define i1 @phi_sgt_non_zero_fail(i8 %x) {
; CHECK-LABEL: @phi_sgt_non_zero_fail(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[X:%.*]], -1
; CHECK-NEXT:    br i1 [[CMP]], label [[T:%.*]], label [[F:%.*]]
; CHECK:       T:
; CHECK-NEXT:    [[V:%.*]] = phi i8 [ [[X]], [[ENTRY:%.*]] ], [ -1, [[F]] ]
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[V]], 0
; CHECK-NEXT:    ret i1 [[R]]
; CHECK:       F:
; CHECK-NEXT:    br label [[T]]
;
entry:
  %cmp = icmp sgt i8 %x, -1
  br i1 %cmp, label %T, label %F
T:
  %v = phi i8 [ %x, %entry], [-1, %F]
  %r = icmp eq i8 %v, 0
  ret i1 %r
F:
  br label %T
}

; An or recurrence with a non-zero start value is never zero.
define i1 @or_recurrence_nonzero_start(ptr %p, i64 %n) {
;
; CHECK-LABEL: @or_recurrence_nonzero_start(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT:    [[ACC:%.*]] = phi i32 [ 32768, [[ENTRY]] ], [ [[ACC_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P:%.*]], i64 [[IV]]
; CHECK-NEXT:    [[X:%.*]] = load i32, ptr [[GEP]], align 4
; CHECK-NEXT:    [[ACC_NEXT]] = or i32 [[X]], [[ACC]]
; CHECK-NEXT:    [[IV_NEXT]] = add i64 [[IV]], 1
; CHECK-NEXT:    [[EC:%.*]] = icmp eq i64 [[IV_NEXT]], [[N:%.*]]
; CHECK-NEXT:    br i1 [[EC]], label [[EXIT:%.*]], label [[LOOP]]
; CHECK:       exit:
; CHECK-NEXT:    ret i1 false
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
  %acc = phi i32 [ 32768, %entry ], [ %acc.next, %loop ]
  %gep = getelementptr i32, ptr %p, i64 %iv
  %x = load i32, ptr %gep
  %acc.next = or i32 %x, %acc
  %iv.next = add i64 %iv, 1
  %ec = icmp eq i64 %iv.next, %n
  br i1 %ec, label %exit, label %loop

exit:
  %cmp = icmp eq i32 %acc.next, 0
  ret i1 %cmp
}

; Negative test: the start value is zero.
define i1 @or_recurrence_zero_start(ptr %p, i64 %n) {
;
; CHECK-LABEL: @or_recurrence_zero_start(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT:    [[ACC:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[ACC_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P:%.*]], i64 [[IV]]
; CHECK-NEXT:    [[X:%.*]] = load i32, ptr [[GEP]], align 4
; CHECK-NEXT:    [[ACC_NEXT]] = or i32 [[X]], [[ACC]]
; CHECK-NEXT:    [[IV_NEXT]] = add i64 [[IV]], 1
; CHECK-NEXT:    [[EC:%.*]] = icmp eq i64 [[IV_NEXT]], [[N:%.*]]
; CHECK-NEXT:    br i1 [[EC]], label [[EXIT:%.*]], label [[LOOP]]
; CHECK:       exit:
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[ACC_NEXT]], 0
; CHECK-NEXT:    ret i1 [[CMP]]
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
  %acc = phi i32 [ 0, %entry ], [ %acc.next, %loop ]
  %gep = getelementptr i32, ptr %p, i64 %iv
  %x = load i32, ptr %gep
  %acc.next = or i32 %x, %acc
  %iv.next = add i64 %iv, 1
  %ec = icmp eq i64 %iv.next, %n
  br i1 %ec, label %exit, label %loop

exit:
  %cmp = icmp eq i32 %acc.next, 0
  ret i1 %cmp
}