llvm-6502/test/Transforms/InstSimplify/compare.ll
Chandler Carruth 70d3bebc8b Add support to ValueTracking for determining that a pointer is non-null
by virtue of inbounds GEPs that preclude a null pointer.

This is a very common pattern in the code generated by std::vector and
other standard library routines which use allocators that test for null
pervasively. This is one step closer to teaching Clang+LLVM to be able
to produce an empty function for:

  void f() {
    std::vector<int> v;
    v.push_back(1);
    v.push_back(2);
    v.push_back(3);
    v.push_back(4);
  }

Which is related to getting them to completely fold SmallVector
push_back sequences into constants when inlining and other optimizations
make that a possibility.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169573 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07 02:08:58 +00:00

650 lines
13 KiB
LLVM

; RUN: opt < %s -instsimplify -S | FileCheck %s
target datalayout = "p:32:32"
define i1 @ptrtoint() {
; CHECK: @ptrtoint
%a = alloca i8
%tmp = ptrtoint i8* %a to i32
%r = icmp eq i32 %tmp, 0
ret i1 %r
; CHECK: ret i1 false
}
define i1 @bitcast() {
; CHECK: @bitcast
%a = alloca i32
%b = alloca i64
%x = bitcast i32* %a to i8*
%y = bitcast i64* %b to i8*
%cmp = icmp eq i8* %x, %y
ret i1 %cmp
; CHECK-NEXT: ret i1 false
}
define i1 @gep() {
; CHECK: @gep
%a = alloca [3 x i8], align 8
%x = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0
%cmp = icmp eq i8* %x, null
ret i1 %cmp
; CHECK-NEXT: ret i1 false
}
define i1 @gep2() {
; CHECK: @gep2
%a = alloca [3 x i8], align 8
%x = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0
%y = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0
%cmp = icmp eq i8* %x, %y
ret i1 %cmp
; CHECK-NEXT: ret i1 true
}
; PR11238
%gept = type { i32, i32 }
@gepy = global %gept zeroinitializer, align 8
@gepz = extern_weak global %gept
define i1 @gep3() {
; CHECK: @gep3
%x = alloca %gept, align 8
%a = getelementptr %gept* %x, i64 0, i32 0
%b = getelementptr %gept* %x, i64 0, i32 1
%equal = icmp eq i32* %a, %b
ret i1 %equal
; CHECK-NEXT: ret i1 false
}
define i1 @gep4() {
; CHECK: @gep4
%x = alloca %gept, align 8
%a = getelementptr %gept* @gepy, i64 0, i32 0
%b = getelementptr %gept* @gepy, i64 0, i32 1
%equal = icmp eq i32* %a, %b
ret i1 %equal
; CHECK-NEXT: ret i1 false
}
define i1 @gep5() {
; CHECK: @gep5
%x = alloca %gept, align 8
%a = getelementptr inbounds %gept* %x, i64 0, i32 1
%b = getelementptr %gept* @gepy, i64 0, i32 0
%equal = icmp eq i32* %a, %b
ret i1 %equal
; CHECK-NEXT: ret i1 false
}
define i1 @gep6(%gept* %x) {
; Same as @gep3 but potentially null.
; CHECK: @gep6
%a = getelementptr %gept* %x, i64 0, i32 0
%b = getelementptr %gept* %x, i64 0, i32 1
%equal = icmp eq i32* %a, %b
ret i1 %equal
; CHECK-NEXT: ret i1 false
}
define i1 @gep7(%gept* %x) {
; CHECK: @gep7
%a = getelementptr %gept* %x, i64 0, i32 0
%b = getelementptr %gept* @gepz, i64 0, i32 0
%equal = icmp eq i32* %a, %b
ret i1 %equal
; CHECK: ret i1 %equal
}
define i1 @gep8(%gept* %x) {
; CHECK: @gep8
%a = getelementptr %gept* %x, i32 1
%b = getelementptr %gept* %x, i32 -1
%equal = icmp ugt %gept* %a, %b
ret i1 %equal
; CHECK: ret i1 %equal
}
define i1 @gep9(i8* %ptr) {
; CHECK: @gep9
; CHECK-NOT: ret
; CHECK: ret i1 true
entry:
%first1 = getelementptr inbounds i8* %ptr, i32 0
%first2 = getelementptr inbounds i8* %first1, i32 1
%first3 = getelementptr inbounds i8* %first2, i32 2
%first4 = getelementptr inbounds i8* %first3, i32 4
%last1 = getelementptr inbounds i8* %first2, i32 48
%last2 = getelementptr inbounds i8* %last1, i32 8
%last3 = getelementptr inbounds i8* %last2, i32 -4
%last4 = getelementptr inbounds i8* %last3, i32 -4
%first.int = ptrtoint i8* %first4 to i32
%last.int = ptrtoint i8* %last4 to i32
%cmp = icmp ne i32 %last.int, %first.int
ret i1 %cmp
}
define i1 @gep10(i8* %ptr) {
; CHECK: @gep10
; CHECK-NOT: ret
; CHECK: ret i1 true
entry:
%first1 = getelementptr inbounds i8* %ptr, i32 -2
%first2 = getelementptr inbounds i8* %first1, i32 44
%last1 = getelementptr inbounds i8* %ptr, i32 48
%last2 = getelementptr inbounds i8* %last1, i32 -6
%first.int = ptrtoint i8* %first2 to i32
%last.int = ptrtoint i8* %last2 to i32
%cmp = icmp eq i32 %last.int, %first.int
ret i1 %cmp
}
define i1 @gep11(i8* %ptr) {
; CHECK: @gep11
; CHECK-NOT: ret
; CHECK: ret i1 true
entry:
%first1 = getelementptr inbounds i8* %ptr, i32 -2
%last1 = getelementptr inbounds i8* %ptr, i32 48
%last2 = getelementptr inbounds i8* %last1, i32 -6
%cmp = icmp ult i8* %first1, %last2
ret i1 %cmp
}
define i1 @gep12(i8* %ptr) {
; CHECK: @gep12
; CHECK-NOT: ret
; CHECK: ret i1 %cmp
entry:
%first1 = getelementptr inbounds i8* %ptr, i32 -2
%last1 = getelementptr inbounds i8* %ptr, i32 48
%last2 = getelementptr inbounds i8* %last1, i32 -6
%cmp = icmp slt i8* %first1, %last2
ret i1 %cmp
}
define i1 @gep13(i8* %ptr) {
; CHECK: @gep13
; We can prove this GEP is non-null because it is inbounds.
%x = getelementptr inbounds i8* %ptr, i32 1
%cmp = icmp eq i8* %x, null
ret i1 %cmp
; CHECK-NEXT: ret i1 false
}
define i1 @gep14({ {}, i8 }* %ptr) {
; CHECK: @gep14
; We can't simplify this because the offset of one in the GEP actually doesn't
; move the pointer.
%x = getelementptr inbounds { {}, i8 }* %ptr, i32 0, i32 1
%cmp = icmp eq i8* %x, null
ret i1 %cmp
; CHECK-NOT: ret i1 false
}
define i1 @gep15({ {}, [4 x {i8, i8}]}* %ptr, i32 %y) {
; CHECK: @gep15
; We can prove this GEP is non-null even though there is a user value, as we
; would necessarily violate inbounds on one side or the other.
%x = getelementptr inbounds { {}, [4 x {i8, i8}]}* %ptr, i32 0, i32 1, i32 %y, i32 1
%cmp = icmp eq i8* %x, null
ret i1 %cmp
; CHECK-NEXT: ret i1 false
}
define i1 @gep16(i8* %ptr, i32 %a) {
; CHECK: @gep16
; We can prove this GEP is non-null because it is inbounds and because we know
; %b is non-zero even though we don't know its value.
%b = or i32 %a, 1
%x = getelementptr inbounds i8* %ptr, i32 %b
%cmp = icmp eq i8* %x, null
ret i1 %cmp
; CHECK-NEXT: ret i1 false
}
define i1 @zext(i32 %x) {
; CHECK: @zext
%e1 = zext i32 %x to i64
%e2 = zext i32 %x to i64
%r = icmp eq i64 %e1, %e2
ret i1 %r
; CHECK: ret i1 true
}
define i1 @zext2(i1 %x) {
; CHECK: @zext2
%e = zext i1 %x to i32
%c = icmp ne i32 %e, 0
ret i1 %c
; CHECK: ret i1 %x
}
define i1 @zext3() {
; CHECK: @zext3
%e = zext i1 1 to i32
%c = icmp ne i32 %e, 0
ret i1 %c
; CHECK: ret i1 true
}
define i1 @sext(i32 %x) {
; CHECK: @sext
%e1 = sext i32 %x to i64
%e2 = sext i32 %x to i64
%r = icmp eq i64 %e1, %e2
ret i1 %r
; CHECK: ret i1 true
}
define i1 @sext2(i1 %x) {
; CHECK: @sext2
%e = sext i1 %x to i32
%c = icmp ne i32 %e, 0
ret i1 %c
; CHECK: ret i1 %x
}
define i1 @sext3() {
; CHECK: @sext3
%e = sext i1 1 to i32
%c = icmp ne i32 %e, 0
ret i1 %c
; CHECK: ret i1 true
}
define i1 @add(i32 %x, i32 %y) {
; CHECK: @add
%l = lshr i32 %x, 1
%q = lshr i32 %y, 1
%r = or i32 %q, 1
%s = add i32 %l, %r
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @add2(i8 %x, i8 %y) {
; CHECK: @add2
%l = or i8 %x, 128
%r = or i8 %y, 129
%s = add i8 %l, %r
%c = icmp eq i8 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @add3(i8 %x, i8 %y) {
; CHECK: @add3
%l = zext i8 %x to i32
%r = zext i8 %y to i32
%s = add i32 %l, %r
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 %c
}
define i1 @add4(i32 %x, i32 %y) {
; CHECK: @add4
%z = add nsw i32 %y, 1
%s1 = add nsw i32 %x, %y
%s2 = add nsw i32 %x, %z
%c = icmp slt i32 %s1, %s2
ret i1 %c
; CHECK: ret i1 true
}
define i1 @add5(i32 %x, i32 %y) {
; CHECK: @add5
%z = add nuw i32 %y, 1
%s1 = add nuw i32 %x, %z
%s2 = add nuw i32 %x, %y
%c = icmp ugt i32 %s1, %s2
ret i1 %c
; CHECK: ret i1 true
}
define i1 @add6(i64 %A, i64 %B) {
; CHECK: @add6
%s1 = add i64 %A, %B
%s2 = add i64 %B, %A
%cmp = icmp eq i64 %s1, %s2
ret i1 %cmp
; CHECK: ret i1 true
}
define i1 @addpowtwo(i32 %x, i32 %y) {
; CHECK: @addpowtwo
%l = lshr i32 %x, 1
%r = shl i32 1, %y
%s = add i32 %l, %r
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @or(i32 %x) {
; CHECK: @or
%o = or i32 %x, 1
%c = icmp eq i32 %o, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @shl(i32 %x) {
; CHECK: @shl
%s = shl i32 1, %x
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @lshr1(i32 %x) {
; CHECK: @lshr1
%s = lshr i32 -1, %x
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @lshr2(i32 %x) {
; CHECK: @lshr2
%s = lshr i32 %x, 30
%c = icmp ugt i32 %s, 8
ret i1 %c
; CHECK: ret i1 false
}
define i1 @ashr1(i32 %x) {
; CHECK: @ashr1
%s = ashr i32 -1, %x
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @ashr2(i32 %x) {
; CHECK: @ashr2
%s = ashr i32 %x, 30
%c = icmp slt i32 %s, -5
ret i1 %c
; CHECK: ret i1 false
}
define i1 @select1(i1 %cond) {
; CHECK: @select1
%s = select i1 %cond, i32 1, i32 0
%c = icmp eq i32 %s, 1
ret i1 %c
; CHECK: ret i1 %cond
}
define i1 @select2(i1 %cond) {
; CHECK: @select2
%x = zext i1 %cond to i32
%s = select i1 %cond, i32 %x, i32 0
%c = icmp ne i32 %s, 0
ret i1 %c
; CHECK: ret i1 %cond
}
define i1 @select3(i1 %cond) {
; CHECK: @select3
%x = zext i1 %cond to i32
%s = select i1 %cond, i32 1, i32 %x
%c = icmp ne i32 %s, 0
ret i1 %c
; CHECK: ret i1 %cond
}
define i1 @select4(i1 %cond) {
; CHECK: @select4
%invert = xor i1 %cond, 1
%s = select i1 %invert, i32 0, i32 1
%c = icmp ne i32 %s, 0
ret i1 %c
; CHECK: ret i1 %cond
}
define i1 @select5(i32 %x) {
; CHECK: @select5
%c = icmp eq i32 %x, 0
%s = select i1 %c, i32 1, i32 %x
%c2 = icmp eq i32 %s, 0
ret i1 %c2
; CHECK: ret i1 false
}
define i1 @select6(i32 %x) {
; CHECK: @select6
%c = icmp sgt i32 %x, 0
%s = select i1 %c, i32 %x, i32 4
%c2 = icmp eq i32 %s, 0
ret i1 %c2
; CHECK: ret i1 %c2
}
define i1 @urem1(i32 %X, i32 %Y) {
; CHECK: @urem1
%A = urem i32 %X, %Y
%B = icmp ult i32 %A, %Y
ret i1 %B
; CHECK: ret i1 true
}
define i1 @urem2(i32 %X, i32 %Y) {
; CHECK: @urem2
%A = urem i32 %X, %Y
%B = icmp eq i32 %A, %Y
ret i1 %B
; CHECK: ret i1 false
}
define i1 @urem3(i32 %X) {
; CHECK: @urem3
%A = urem i32 %X, 10
%B = icmp ult i32 %A, 15
ret i1 %B
; CHECK: ret i1 true
}
define i1 @urem4(i32 %X) {
; CHECK: @urem4
%A = urem i32 %X, 15
%B = icmp ult i32 %A, 10
ret i1 %B
; CHECK: ret i1 %B
}
define i1 @urem5(i16 %X, i32 %Y) {
; CHECK: @urem5
%A = zext i16 %X to i32
%B = urem i32 %A, %Y
%C = icmp slt i32 %B, %Y
ret i1 %C
; CHECK: ret i1 true
}
define i1 @urem6(i32 %X, i32 %Y) {
; CHECK: @urem6
%A = urem i32 %X, %Y
%B = icmp ugt i32 %Y, %A
ret i1 %B
; CHECK: ret i1 true
}
define i1 @srem1(i32 %X) {
; CHECK: @srem1
%A = srem i32 %X, -5
%B = icmp sgt i32 %A, 5
ret i1 %B
; CHECK: ret i1 false
}
; PR9343 #15
; CHECK: @srem2
; CHECK: ret i1 false
define i1 @srem2(i16 %X, i32 %Y) {
%A = zext i16 %X to i32
%B = add nsw i32 %A, 1
%C = srem i32 %B, %Y
%D = icmp slt i32 %C, 0
ret i1 %D
}
; CHECK: @srem3
; CHECK-NEXT: ret i1 false
define i1 @srem3(i16 %X, i32 %Y) {
%A = zext i16 %X to i32
%B = or i32 2147483648, %A
%C = sub nsw i32 1, %B
%D = srem i32 %C, %Y
%E = icmp slt i32 %D, 0
ret i1 %E
}
define i1 @udiv1(i32 %X) {
; CHECK: @udiv1
%A = udiv i32 %X, 1000000
%B = icmp ult i32 %A, 5000
ret i1 %B
; CHECK: ret i1 true
}
define i1 @udiv2(i32 %X, i32 %Y, i32 %Z) {
; CHECK: @udiv2
%A = udiv exact i32 10, %Z
%B = udiv exact i32 20, %Z
%C = icmp ult i32 %A, %B
ret i1 %C
; CHECK: ret i1 true
}
define i1 @udiv3(i32 %X, i32 %Y) {
; CHECK: @udiv3
%A = udiv i32 %X, %Y
%C = icmp ugt i32 %A, %X
ret i1 %C
; CHECK: ret i1 false
}
define i1 @udiv4(i32 %X, i32 %Y) {
; CHECK: @udiv4
%A = udiv i32 %X, %Y
%C = icmp ule i32 %A, %X
ret i1 %C
; CHECK: ret i1 true
}
define i1 @udiv5(i32 %X) {
; CHECK: @udiv5
%A = udiv i32 123, %X
%C = icmp ugt i32 %A, 124
ret i1 %C
; CHECK: ret i1 false
}
; PR11340
define i1 @udiv6(i32 %X) nounwind {
; CHECK: @udiv6
%A = udiv i32 1, %X
%C = icmp eq i32 %A, 0
ret i1 %C
; CHECK: ret i1 %C
}
define i1 @sdiv1(i32 %X) {
; CHECK: @sdiv1
%A = sdiv i32 %X, 1000000
%B = icmp slt i32 %A, 3000
ret i1 %B
; CHECK: ret i1 true
}
define i1 @or1(i32 %X) {
; CHECK: @or1
%A = or i32 %X, 62
%B = icmp ult i32 %A, 50
ret i1 %B
; CHECK: ret i1 false
}
define i1 @and1(i32 %X) {
; CHECK: @and1
%A = and i32 %X, 62
%B = icmp ugt i32 %A, 70
ret i1 %B
; CHECK: ret i1 false
}
define i1 @mul1(i32 %X) {
; CHECK: @mul1
; Square of a non-zero number is non-zero if there is no overflow.
%Y = or i32 %X, 1
%M = mul nuw i32 %Y, %Y
%C = icmp eq i32 %M, 0
ret i1 %C
; CHECK: ret i1 false
}
define i1 @mul2(i32 %X) {
; CHECK: @mul2
; Square of a non-zero number is positive if there is no signed overflow.
%Y = or i32 %X, 1
%M = mul nsw i32 %Y, %Y
%C = icmp sgt i32 %M, 0
ret i1 %C
; CHECK: ret i1 true
}
define i1 @mul3(i32 %X, i32 %Y) {
; CHECK: @mul3
; Product of non-negative numbers is non-negative if there is no signed overflow.
%XX = mul nsw i32 %X, %X
%YY = mul nsw i32 %Y, %Y
%M = mul nsw i32 %XX, %YY
%C = icmp sge i32 %M, 0
ret i1 %C
; CHECK: ret i1 true
}
define <2 x i1> @vectorselect1(<2 x i1> %cond) {
; CHECK: @vectorselect1
%invert = xor <2 x i1> %cond, <i1 1, i1 1>
%s = select <2 x i1> %invert, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 1, i32 1>
%c = icmp ne <2 x i32> %s, <i32 0, i32 0>
ret <2 x i1> %c
; CHECK: ret <2 x i1> %cond
}
; PR11948
define <2 x i1> @vectorselectcrash(i32 %arg1) {
%tobool40 = icmp ne i32 %arg1, 0
%cond43 = select i1 %tobool40, <2 x i16> <i16 -5, i16 66>, <2 x i16> <i16 46, i16 1>
%cmp45 = icmp ugt <2 x i16> %cond43, <i16 73, i16 21>
ret <2 x i1> %cmp45
}
; PR12013
define i1 @alloca_compare(i64 %idx) {
%sv = alloca { i32, i32, [124 x i32] }
%1 = getelementptr inbounds { i32, i32, [124 x i32] }* %sv, i32 0, i32 2, i64 %idx
%2 = icmp eq i32* %1, null
ret i1 %2
; CHECK: alloca_compare
; CHECK: ret i1 false
}
; PR12075
define i1 @infinite_gep() {
ret i1 1
unreachableblock:
%X = getelementptr i32 *%X, i32 1
%Y = icmp eq i32* %X, null
ret i1 %Y
}