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| ; RUN: opt < %s -gvn -S | FileCheck %s
%struct.A = type { i32 (...)** }
@_ZTV1A = available_externally unnamed_addr constant [3 x i8*] [i8* null, i8* bitcast (i8** @_ZTI1A to i8*), i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)], align 8
@_ZTI1A = external constant i8*
@unknownPtr = external global i8
; CHECK-LABEL: define i8 @simple() {
define i8 @simple() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0
%b = load i8, i8* %ptr, !invariant.group !0
%c = load i8, i8* %ptr, !invariant.group !0
; CHECK: ret i8 42
ret i8 %a
}
; CHECK-LABEL: define i8 @optimizable1() {
define i8 @optimizable1() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
%ptr2 = call i8* @llvm.launder.invariant.group.p0i8(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr2); call to use %ptr2
; CHECK: ret i8 42
ret i8 %a
}
; CHECK-LABEL: define i8 @optimizable2() {
define i8 @optimizable2() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr)
store i8 13, i8* %ptr ; can't use this store with invariant.group
%a = load i8, i8* %ptr
call void @bar(i8 %a) ; call to use %a
call void @foo(i8* %ptr)
%b = load i8, i8* %ptr, !invariant.group !0
; CHECK: ret i8 42
ret i8 %b
}
; CHECK-LABEL: define i1 @proveEqualityForStrip(
define i1 @proveEqualityForStrip(i8* %a) {
; FIXME: The first call could be also removed by GVN. Right now
; DCE removes it. The second call is CSE'd with the first one.
; CHECK: %b1 = call i8* @llvm.strip.invariant.group.p0i8(i8* %a)
%b1 = call i8* @llvm.strip.invariant.group.p0i8(i8* %a)
; CHECK-NOT: llvm.strip.invariant.group
%b2 = call i8* @llvm.strip.invariant.group.p0i8(i8* %a)
%r = icmp eq i8* %b1, %b2
; CHECK: ret i1 true
ret i1 %r
}
; CHECK-LABEL: define i8 @unoptimizable1() {
define i8 @unoptimizable1() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0
; CHECK: ret i8 %a
ret i8 %a
}
; CHECK-LABEL: define void @indirectLoads() {
define void @indirectLoads() {
entry:
%a = alloca %struct.A*, align 8
%0 = bitcast %struct.A** %a to i8*
%call = call i8* @getPointer(i8* null)
%1 = bitcast i8* %call to %struct.A*
call void @_ZN1AC1Ev(%struct.A* %1)
%2 = bitcast %struct.A* %1 to i8***
; CHECK: %vtable = load {{.*}} !invariant.group
%vtable = load i8**, i8*** %2, align 8, !invariant.group !0
%cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([3 x i8*], [3 x i8*]* @_ZTV1A, i64 0, i64 2)
call void @llvm.assume(i1 %cmp.vtables)
store %struct.A* %1, %struct.A** %a, align 8
%3 = load %struct.A*, %struct.A** %a, align 8
%4 = bitcast %struct.A* %3 to void (%struct.A*)***
; CHECK: call void @_ZN1A3fooEv(
%vtable1 = load void (%struct.A*)**, void (%struct.A*)*** %4, align 8, !invariant.group !0
%vfn = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** %vtable1, i64 0
%5 = load void (%struct.A*)*, void (%struct.A*)** %vfn, align 8
call void %5(%struct.A* %3)
%6 = load %struct.A*, %struct.A** %a, align 8
%7 = bitcast %struct.A* %6 to void (%struct.A*)***
; CHECK: call void @_ZN1A3fooEv(
%vtable2 = load void (%struct.A*)**, void (%struct.A*)*** %7, align 8, !invariant.group !0
%vfn3 = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** %vtable2, i64 0
%8 = load void (%struct.A*)*, void (%struct.A*)** %vfn3, align 8
call void %8(%struct.A* %6)
%9 = load %struct.A*, %struct.A** %a, align 8
%10 = bitcast %struct.A* %9 to void (%struct.A*)***
%vtable4 = load void (%struct.A*)**, void (%struct.A*)*** %10, align 8, !invariant.group !0
%vfn5 = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** %vtable4, i64 0
%11 = load void (%struct.A*)*, void (%struct.A*)** %vfn5, align 8
; CHECK: call void @_ZN1A3fooEv(
call void %11(%struct.A* %9)
%vtable5 = load i8**, i8*** %2, align 8, !invariant.group !0
%vfn6 = getelementptr inbounds i8*, i8** %vtable5, i64 0
%12 = bitcast i8** %vfn6 to void (%struct.A*)**
%13 = load void (%struct.A*)*, void (%struct.A*)** %12, align 8
; CHECK: call void @_ZN1A3fooEv(
call void %13(%struct.A* %9)
ret void
}
; CHECK-LABEL: define void @combiningBitCastWithLoad() {
define void @combiningBitCastWithLoad() {
entry:
%a = alloca %struct.A*, align 8
%0 = bitcast %struct.A** %a to i8*
%call = call i8* @getPointer(i8* null)
%1 = bitcast i8* %call to %struct.A*
call void @_ZN1AC1Ev(%struct.A* %1)
%2 = bitcast %struct.A* %1 to i8***
; CHECK: %vtable = load {{.*}} !invariant.group
%vtable = load i8**, i8*** %2, align 8, !invariant.group !0
%cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([3 x i8*], [3 x i8*]* @_ZTV1A, i64 0, i64 2)
store %struct.A* %1, %struct.A** %a, align 8
; CHECK-NOT: !invariant.group
%3 = load %struct.A*, %struct.A** %a, align 8
%4 = bitcast %struct.A* %3 to void (%struct.A*)***
%vtable1 = load void (%struct.A*)**, void (%struct.A*)*** %4, align 8, !invariant.group !0
%vfn = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** %vtable1, i64 0
%5 = load void (%struct.A*)*, void (%struct.A*)** %vfn, align 8
call void %5(%struct.A* %3)
ret void
}
; CHECK-LABEL:define void @loadCombine() {
define void @loadCombine() {
enter:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
; CHECK: %[[A:.*]] = load i8, i8* %ptr, !invariant.group
%a = load i8, i8* %ptr, !invariant.group !0
; CHECK-NOT: load
%b = load i8, i8* %ptr, !invariant.group !0
; CHECK: call void @bar(i8 %[[A]])
call void @bar(i8 %a)
; CHECK: call void @bar(i8 %[[A]])
call void @bar(i8 %b)
ret void
}
; CHECK-LABEL: define void @loadCombine1() {
define void @loadCombine1() {
enter:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
; CHECK: %[[D:.*]] = load i8, i8* %ptr, !invariant.group
%c = load i8, i8* %ptr
; CHECK-NOT: load
%d = load i8, i8* %ptr, !invariant.group !0
; CHECK: call void @bar(i8 %[[D]])
call void @bar(i8 %c)
; CHECK: call void @bar(i8 %[[D]])
call void @bar(i8 %d)
ret void
}
; CHECK-LABEL: define void @loadCombine2() {
define void @loadCombine2() {
enter:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
; CHECK: %[[E:.*]] = load i8, i8* %ptr, !invariant.group
%e = load i8, i8* %ptr, !invariant.group !0
; CHECK-NOT: load
%f = load i8, i8* %ptr
; CHECK: call void @bar(i8 %[[E]])
call void @bar(i8 %e)
; CHECK: call void @bar(i8 %[[E]])
call void @bar(i8 %f)
ret void
}
; CHECK-LABEL: define void @loadCombine3() {
define void @loadCombine3() {
enter:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
; CHECK: %[[E:.*]] = load i8, i8* %ptr, !invariant.group
%e = load i8, i8* %ptr, !invariant.group !0
; CHECK-NOT: load
%f = load i8, i8* %ptr, !invariant.group !0
; CHECK: call void @bar(i8 %[[E]])
call void @bar(i8 %e)
; CHECK: call void @bar(i8 %[[E]])
call void @bar(i8 %f)
ret void
}
; CHECK-LABEL: define i8 @unoptimizable2() {
define i8 @unoptimizable2() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr
call void @foo(i8* %ptr)
%b = load i8, i8* %ptr, !invariant.group !0
; CHECK: ret i8 %a
ret i8 %a
}
; CHECK-LABEL: define i8 @unoptimizable3() {
define i8 @unoptimizable3() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
%ptr2 = call i8* @getPointer(i8* %ptr)
%a = load i8, i8* %ptr2, !invariant.group !0
; CHECK: ret i8 %a
ret i8 %a
}
; CHECK-LABEL: define i8 @optimizable4() {
define i8 @optimizable4() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
%ptr2 = call i8* @llvm.launder.invariant.group.p0i8(i8* %ptr)
; CHECK-NOT: load
%a = load i8, i8* %ptr2, !invariant.group !0
; CHECK: ret i8 42
ret i8 %a
}
; CHECK-LABEL: define i8 @volatile1() {
define i8 @volatile1() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0
%b = load volatile i8, i8* %ptr
; CHECK: call void @bar(i8 %b)
call void @bar(i8 %b)
%c = load volatile i8, i8* %ptr, !invariant.group !0
; FIXME: we could change %c to 42, preserving volatile load
; CHECK: call void @bar(i8 %c)
call void @bar(i8 %c)
; CHECK: ret i8 42
ret i8 %a
}
; CHECK-LABEL: define i8 @volatile2() {
define i8 @volatile2() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0
%b = load volatile i8, i8* %ptr
; CHECK: call void @bar(i8 %b)
call void @bar(i8 %b)
%c = load volatile i8, i8* %ptr, !invariant.group !0
; FIXME: we could change %c to 42, preserving volatile load
; CHECK: call void @bar(i8 %c)
call void @bar(i8 %c)
; CHECK: ret i8 42
ret i8 %a
}
; CHECK-LABEL: define i8 @fun() {
define i8 @fun() {
entry:
%ptr = alloca i8
store i8 42, i8* %ptr, !invariant.group !0
call void @foo(i8* %ptr)
%a = load i8, i8* %ptr, !invariant.group !0 ; Can assume that value under %ptr didn't change
; CHECK: call void @bar(i8 42)
call void @bar(i8 %a)
%newPtr = call i8* @getPointer(i8* %ptr)
%c = load i8, i8* %newPtr, !invariant.group !0 ; Can't assume anything, because we only have information about %ptr
; CHECK: call void @bar(i8 %c)
call void @bar(i8 %c)
%unknownValue = load i8, i8* @unknownPtr
; FIXME: Can assume that %unknownValue == 42
; CHECK: store i8 %unknownValue, i8* %ptr, !invariant.group !0
store i8 %unknownValue, i8* %ptr, !invariant.group !0
%newPtr2 = call i8* @llvm.launder.invariant.group.p0i8(i8* %ptr)
; CHECK-NOT: load
%d = load i8, i8* %newPtr2, !invariant.group !0
; CHECK: ret i8 %unknownValue
ret i8 %d
}
; This test checks if invariant.group understands gep with zeros
; CHECK-LABEL: define void @testGEP0() {
define void @testGEP0() {
%a = alloca %struct.A, align 8
%1 = bitcast %struct.A* %a to i8*
%2 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 0
store i32 (...)** bitcast (i8** getelementptr inbounds ([3 x i8*], [3 x i8*]* @_ZTV1A, i64 0, i64 2) to i32 (...)**), i32 (...)*** %2, align 8, !invariant.group !0
; CHECK: call void @_ZN1A3fooEv(%struct.A* nonnull dereferenceable(8) %a)
call void @_ZN1A3fooEv(%struct.A* nonnull dereferenceable(8) %a) ; This call may change vptr
%3 = load i8, i8* @unknownPtr, align 4
%4 = icmp eq i8 %3, 0
br i1 %4, label %_Z1gR1A.exit, label %5
; This should be devirtualized by invariant.group
%6 = bitcast %struct.A* %a to void (%struct.A*)***
%7 = load void (%struct.A*)**, void (%struct.A*)*** %6, align 8, !invariant.group !0
%8 = load void (%struct.A*)*, void (%struct.A*)** %7, align 8
; CHECK: call void @_ZN1A3fooEv(%struct.A* nonnull %a)
call void %8(%struct.A* nonnull %a)
br label %_Z1gR1A.exit
_Z1gR1A.exit: ; preds = %0, %5
ret void
}
; Check if no optimizations are performed with global pointers.
; FIXME: we could do the optimizations if we would check if dependency comes
; from the same function.
; CHECK-LABEL: define void @testGlobal() {
define void @testGlobal() {
; CHECK: %a = load i8, i8* @unknownPtr, !invariant.group !0
%a = load i8, i8* @unknownPtr, !invariant.group !0
call void @foo2(i8* @unknownPtr, i8 %a)
; CHECK: %1 = load i8, i8* @unknownPtr, !invariant.group !0
%1 = load i8, i8* @unknownPtr, !invariant.group !0
call void @bar(i8 %1)
%b0 = bitcast i8* @unknownPtr to i1*
call void @fooBit(i1* %b0, i1 1)
; Adding regex because of canonicalization of bitcasts
; CHECK: %2 = load i1, i1* {{.*}}, !invariant.group !0
%2 = load i1, i1* %b0, !invariant.group !0
call void @fooBit(i1* %b0, i1 %2)
; CHECK: %3 = load i1, i1* {{.*}}, !invariant.group !0
%3 = load i1, i1* %b0, !invariant.group !0
call void @fooBit(i1* %b0, i1 %3)
ret void
}
; And in the case it is not global
; CHECK-LABEL: define void @testNotGlobal() {
define void @testNotGlobal() {
%a = alloca i8
call void @foo(i8* %a)
; CHECK: %b = load i8, i8* %a, !invariant.group !0
%b = load i8, i8* %a, !invariant.group !0
call void @foo2(i8* %a, i8 %b)
%1 = load i8, i8* %a, !invariant.group !0
; CHECK: call void @bar(i8 %b)
call void @bar(i8 %1)
%b0 = bitcast i8* %a to i1*
call void @fooBit(i1* %b0, i1 1)
; CHECK: %1 = trunc i8 %b to i1
%2 = load i1, i1* %b0, !invariant.group !0
; CHECK-NEXT: call void @fooBit(i1* %b0, i1 %1)
call void @fooBit(i1* %b0, i1 %2)
%3 = load i1, i1* %b0, !invariant.group !0
; CHECK-NEXT: call void @fooBit(i1* %b0, i1 %1)
call void @fooBit(i1* %b0, i1 %3)
ret void
}
; CHECK-LABEL: define void @handling_loops()
define void @handling_loops() {
%a = alloca %struct.A, align 8
%1 = bitcast %struct.A* %a to i8*
%2 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 0
store i32 (...)** bitcast (i8** getelementptr inbounds ([3 x i8*], [3 x i8*]* @_ZTV1A, i64 0, i64 2) to i32 (...)**), i32 (...)*** %2, align 8, !invariant.group !0
%3 = load i8, i8* @unknownPtr, align 4
%4 = icmp sgt i8 %3, 0
br i1 %4, label %.lr.ph.i, label %_Z2g2R1A.exit
.lr.ph.i: ; preds = %0
%5 = bitcast %struct.A* %a to void (%struct.A*)***
%6 = load i8, i8* @unknownPtr, align 4
%7 = icmp sgt i8 %6, 1
br i1 %7, label %._crit_edge.preheader, label %_Z2g2R1A.exit
._crit_edge.preheader: ; preds = %.lr.ph.i
br label %._crit_edge
._crit_edge: ; preds = %._crit_edge.preheader, %._crit_edge
%8 = phi i8 [ %10, %._crit_edge ], [ 1, %._crit_edge.preheader ]
%.pre = load void (%struct.A*)**, void (%struct.A*)*** %5, align 8, !invariant.group !0
%9 = load void (%struct.A*)*, void (%struct.A*)** %.pre, align 8
; CHECK: call void @_ZN1A3fooEv(%struct.A* nonnull %a)
call void %9(%struct.A* nonnull %a) #3
; CHECK-NOT: call void %
%10 = add nuw nsw i8 %8, 1
%11 = load i8, i8* @unknownPtr, align 4
%12 = icmp slt i8 %10, %11
br i1 %12, label %._crit_edge, label %_Z2g2R1A.exit.loopexit
_Z2g2R1A.exit.loopexit: ; preds = %._crit_edge
br label %_Z2g2R1A.exit
_Z2g2R1A.exit: ; preds = %_Z2g2R1A.exit.loopexit, %.lr.ph.i, %0
ret void
}
declare void @foo(i8*)
declare void @foo2(i8*, i8)
declare void @bar(i8)
declare i8* @getPointer(i8*)
declare void @_ZN1A3fooEv(%struct.A*)
declare void @_ZN1AC1Ev(%struct.A*)
declare void @fooBit(i1*, i1)
declare i8* @llvm.launder.invariant.group.p0i8(i8*)
declare i8* @llvm.strip.invariant.group.p0i8(i8*)
declare void @llvm.assume(i1 %cmp.vtables)
!0 = !{} |