sink-common-code.ll
15.3 KB
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; RUN: opt < %s -gvn-sink -simplifycfg -simplifycfg-sink-common=false -S | FileCheck %s
define zeroext i1 @test1(i1 zeroext %flag, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
br i1 %flag, label %if.then, label %if.else
; CHECK-LABEL: test1
; CHECK: add
; CHECK: select
; CHECK: icmp
; CHECK-NOT: br
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
br label %if.end
if.else:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = zext i1 %cmp2 to i8
br label %if.end
if.end:
%obeys.0 = phi i8 [ %frombool1, %if.then ], [ %frombool3, %if.else ]
%tobool4 = icmp ne i8 %obeys.0, 0
ret i1 %tobool4
}
define zeroext i1 @test2(i1 zeroext %flag, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
br i1 %flag, label %if.then, label %if.else
; CHECK-LABEL: test2
; CHECK: add
; CHECK: select
; CHECK: icmp
; CHECK-NOT: br
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
br label %if.end
if.else:
%add = add i32 %nblks, %blksB
%cmp2 = icmp uge i32 %blksA, %add
%frombool3 = zext i1 %cmp2 to i8
br label %if.end
if.end:
%obeys.0 = phi i8 [ %frombool1, %if.then ], [ %frombool3, %if.else ]
%tobool4 = icmp ne i8 %obeys.0, 0
ret i1 %tobool4
}
declare i32 @foo(i32, i32) nounwind readnone
; FIXME: The test failes when the original order of the
; candidates with the same cost is preserved.
;
;define i32 @test3(i1 zeroext %flag, i32 %x, i32 %y) {
;entry:
; br i1 %flag, label %if.then, label %if.else
;
;if.then:
; %x0 = call i32 @foo(i32 %x, i32 0) nounwind readnone
; %y0 = call i32 @foo(i32 %x, i32 1) nounwind readnone
; br label %if.end
;
;if.else:
; %x1 = call i32 @foo(i32 %y, i32 0) nounwind readnone
; %y1 = call i32 @foo(i32 %y, i32 1) nounwind readnone
; br label %if.end
;
;if.end:
; %xx = phi i32 [ %x0, %if.then ], [ %x1, %if.else ]
; %yy = phi i32 [ %y0, %if.then ], [ %y1, %if.else ]
; %ret = add i32 %xx, %yy
; ret i32 %ret
;}
;
; -CHECK-LABEL: test3
; -CHECK: select
; -CHECK: call
; -CHECK: call
; -CHECK: add
; -CHECK-NOT: br
define i32 @test4(i1 zeroext %flag, i32 %x, i32* %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%a = add i32 %x, 5
store i32 %a, i32* %y
br label %if.end
if.else:
%b = add i32 %x, 7
store i32 %b, i32* %y
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test4
; CHECK: select
; CHECK: store
; CHECK-NOT: store
define i32 @test5(i1 zeroext %flag, i32 %x, i32* %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%a = add i32 %x, 5
store volatile i32 %a, i32* %y
br label %if.end
if.else:
%b = add i32 %x, 7
store i32 %b, i32* %y
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test5
; CHECK: store volatile
; CHECK: store
define i32 @test6(i1 zeroext %flag, i32 %x, i32* %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%a = add i32 %x, 5
store volatile i32 %a, i32* %y
br label %if.end
if.else:
%b = add i32 %x, 7
store volatile i32 %b, i32* %y
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test6
; CHECK: select
; CHECK: store volatile
; CHECK-NOT: store
define i32 @test7(i1 zeroext %flag, i32 %x, i32* %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%z = load volatile i32, i32* %y
%a = add i32 %z, 5
store volatile i32 %a, i32* %y
br label %if.end
if.else:
%w = load volatile i32, i32* %y
%b = add i32 %w, 7
store volatile i32 %b, i32* %y
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test7
; CHECK-DAG: select
; CHECK-DAG: load volatile
; CHECK: store volatile
; CHECK-NOT: load
; CHECK-NOT: store
; The extra store in %if.then means %z and %w are not equivalent.
define i32 @test9(i1 zeroext %flag, i32 %x, i32* %y, i32* %p) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
store i32 7, i32* %p
%z = load volatile i32, i32* %y
store i32 6, i32* %p
%a = add i32 %z, 5
store volatile i32 %a, i32* %y
br label %if.end
if.else:
%w = load volatile i32, i32* %y
%b = add i32 %w, 7
store volatile i32 %b, i32* %y
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test9
; CHECK: add
; CHECK: add
%struct.anon = type { i32, i32 }
; The GEP indexes a struct type so cannot have a variable last index.
define i32 @test10(i1 zeroext %flag, i32 %x, i32* %y, %struct.anon* %s) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%dummy = add i32 %x, 5
%gepa = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 0
store volatile i32 %x, i32* %gepa
br label %if.end
if.else:
%dummy1 = add i32 %x, 6
%gepb = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 1
store volatile i32 %x, i32* %gepb
br label %if.end
if.end:
ret i32 1
}
; CHECK-LABEL: test10
; CHECK: getelementptr
; CHECK: store volatile
; CHECK: getelementptr
; CHECK: store volatile
; The shufflevector's mask operand cannot be merged in a PHI.
define i32 @test11(i1 zeroext %flag, i32 %w, <2 x i32> %x, <2 x i32> %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%dummy = add i32 %w, 5
%sv1 = shufflevector <2 x i32> %x, <2 x i32> %y, <2 x i32> <i32 0, i32 1>
br label %if.end
if.else:
%dummy1 = add i32 %w, 6
%sv2 = shufflevector <2 x i32> %x, <2 x i32> %y, <2 x i32> <i32 1, i32 0>
br label %if.end
if.end:
%p = phi <2 x i32> [ %sv1, %if.then ], [ %sv2, %if.else ]
ret i32 1
}
; CHECK-LABEL: test11
; CHECK: shufflevector
; CHECK: shufflevector
; We can't common an intrinsic!
define i32 @test12(i1 zeroext %flag, i32 %w, i32 %x, i32 %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%dummy = add i32 %w, 5
%sv1 = call i32 @llvm.ctlz.i32(i32 %x)
br label %if.end
if.else:
%dummy1 = add i32 %w, 6
%sv2 = call i32 @llvm.cttz.i32(i32 %x)
br label %if.end
if.end:
%p = phi i32 [ %sv1, %if.then ], [ %sv2, %if.else ]
ret i32 1
}
declare i32 @llvm.ctlz.i32(i32 %x) readnone
declare i32 @llvm.cttz.i32(i32 %x) readnone
; CHECK-LABEL: test12
; CHECK: call i32 @llvm.ctlz
; CHECK: call i32 @llvm.cttz
; The TBAA metadata should be properly combined.
define i32 @test13(i1 zeroext %flag, i32 %x, i32* %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%z = load volatile i32, i32* %y
%a = add i32 %z, 5
store volatile i32 %a, i32* %y, !tbaa !3
br label %if.end
if.else:
%w = load volatile i32, i32* %y
%b = add i32 %w, 7
store volatile i32 %b, i32* %y, !tbaa !4
br label %if.end
if.end:
ret i32 1
}
!0 = !{ !"an example type tree" }
!1 = !{ !"int", !0 }
!2 = !{ !"float", !0 }
!3 = !{ !"const float", !2, i64 0 }
!4 = !{ !"special float", !2, i64 1 }
; CHECK-LABEL: test13
; CHECK-DAG: select
; CHECK-DAG: load volatile
; CHECK: store volatile {{.*}}, !tbaa !0
; CHECK-NOT: load
; CHECK-NOT: store
; The call should be commoned.
define i32 @test13a(i1 zeroext %flag, i32 %w, i32 %x, i32 %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%sv1 = call i32 @bar(i32 %x)
br label %if.end
if.else:
%sv2 = call i32 @bar(i32 %y)
br label %if.end
if.end:
%p = phi i32 [ %sv1, %if.then ], [ %sv2, %if.else ]
ret i32 1
}
declare i32 @bar(i32)
; CHECK-LABEL: test13a
; CHECK: %[[x:.*]] = select i1 %flag
; CHECK: call i32 @bar(i32 %[[x]])
; The load should be commoned.
define i32 @test14(i1 zeroext %flag, i32 %w, i32 %x, i32 %y, %struct.anon* %s) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%dummy = add i32 %x, 1
%gepa = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 1
%sv1 = load i32, i32* %gepa
%cmp1 = icmp eq i32 %sv1, 56
br label %if.end
if.else:
%dummy2 = add i32 %x, 4
%gepb = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 1
%sv2 = load i32, i32* %gepb
%cmp2 = icmp eq i32 %sv2, 57
br label %if.end
if.end:
%p = phi i1 [ %cmp1, %if.then ], [ %cmp2, %if.else ]
ret i32 1
}
; CHECK-LABEL: test14
; CHECK: getelementptr
; CHECK: load
; CHECK-NOT: load
; The load should be commoned.
define i32 @test15(i1 zeroext %flag, i32 %w, i32 %x, i32 %y, %struct.anon* %s) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%dummy = add i32 %x, 1
%gepa = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 0
%sv1 = load i32, i32* %gepa
%ext1 = zext i32 %sv1 to i64
%cmp1 = icmp eq i64 %ext1, 56
br label %if.end
if.else:
%dummy2 = add i32 %x, 4
%gepb = getelementptr inbounds %struct.anon, %struct.anon* %s, i32 0, i32 1
%sv2 = load i32, i32* %gepb
%ext2 = zext i32 %sv2 to i64
%cmp2 = icmp eq i64 %ext2, 56
br label %if.end
if.end:
%p = phi i1 [ %cmp1, %if.then ], [ %cmp2, %if.else ]
ret i32 1
}
; CHECK-LABEL: test15
; CHECK: getelementptr
; CHECK: load
; CHECK-NOT: load
define zeroext i1 @test_crash(i1 zeroext %flag, i32* %i4, i32* %m, i32* %n) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%tmp1 = load i32, i32* %i4
%tmp2 = add i32 %tmp1, -1
store i32 %tmp2, i32* %i4
br label %if.end
if.else:
%tmp3 = load i32, i32* %m
%tmp4 = load i32, i32* %n
%tmp5 = add i32 %tmp3, %tmp4
store i32 %tmp5, i32* %i4
br label %if.end
if.end:
ret i1 true
}
; CHECK-LABEL: test_crash
; No checks for test_crash - just ensure it doesn't crash!
define zeroext i1 @test16(i1 zeroext %flag, i1 zeroext %flag2, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
br label %if.end
if.else:
br i1 %flag2, label %if.then2, label %if.end
if.then2:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = zext i1 %cmp2 to i8
br label %if.end
if.end:
%obeys.0 = phi i8 [ %frombool1, %if.then ], [ %frombool3, %if.then2 ], [ 0, %if.else ]
%tobool4 = icmp ne i8 %obeys.0, 0
ret i1 %tobool4
}
; CHECK-LABEL: test16
; CHECK: zext
; CHECK: zext
define zeroext i1 @test16a(i1 zeroext %flag, i1 zeroext %flag2, i32 %blksA, i32 %blksB, i32 %nblks, i8* %p) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
%b1 = sext i8 %frombool1 to i32
%b2 = trunc i32 %b1 to i8
store i8 %b2, i8* %p
br label %if.end
if.else:
br i1 %flag2, label %if.then2, label %if.end
if.then2:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = zext i1 %cmp2 to i8
%a1 = sext i8 %frombool3 to i32
%a2 = trunc i32 %a1 to i8
store i8 %a2, i8* %p
br label %if.end
if.end:
ret i1 true
}
; CHECK-LABEL: test16a
; CHECK: zext
; CHECK-NOT: zext
define zeroext i1 @test17(i32 %flag, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
switch i32 %flag, label %if.end [
i32 0, label %if.then
i32 1, label %if.then2
]
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = call i8 @i1toi8(i1 %cmp)
%a1 = sext i8 %frombool1 to i32
%a2 = trunc i32 %a1 to i8
br label %if.end
if.then2:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = call i8 @i1toi8(i1 %cmp2)
%b1 = sext i8 %frombool3 to i32
%b2 = trunc i32 %b1 to i8
br label %if.end
if.end:
%obeys.0 = phi i8 [ %a2, %if.then ], [ %b2, %if.then2 ], [ 0, %entry ]
%tobool4 = icmp ne i8 %obeys.0, 0
ret i1 %tobool4
}
declare i8 @i1toi8(i1)
; FIXME: DISABLED - we don't consider this profitable. We should
; - Consider argument setup/return mov'ing for calls, like InlineCost does.
; - Consider the removal of the %obeys.0 PHI (zero PHI movement overall)
; DISABLED-CHECK-LABEL: test17
; DISABLED-CHECK: if.then:
; DISABLED-CHECK-NEXT: icmp uge
; DISABLED-CHECK-NEXT: br label %[[x:.*]]
; DISABLED-CHECK: if.then2:
; DISABLED-CHECK-NEXT: add
; DISABLED-CHECK-NEXT: icmp ule
; DISABLED-CHECK-NEXT: br label %[[x]]
; DISABLED-CHECK: [[x]]:
; DISABLED-CHECK-NEXT: %[[y:.*]] = phi i1 [ %cmp
; DISABLED-CHECK-NEXT: %[[z:.*]] = call i8 @i1toi8(i1 %[[y]])
; DISABLED-CHECK-NEXT: br label %if.end
; DISABLED-CHECK: if.end:
; DISABLED-CHECK-NEXT: phi i8
; DISABLED-CHECK-DAG: [ %[[z]], %[[x]] ]
; DISABLED-CHECK-DAG: [ 0, %entry ]
define zeroext i1 @test18(i32 %flag, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
switch i32 %flag, label %if.then3 [
i32 0, label %if.then
i32 1, label %if.then2
]
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
br label %if.end
if.then2:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = zext i1 %cmp2 to i8
br label %if.end
if.then3:
%add2 = add i32 %nblks, %blksA
%cmp3 = icmp ule i32 %add2, %blksA
%frombool4 = zext i1 %cmp3 to i8
br label %if.end
if.end:
%obeys.0 = phi i8 [ %frombool1, %if.then ], [ %frombool3, %if.then2 ], [ %frombool4, %if.then3 ]
%tobool4 = icmp ne i8 %obeys.0, 0
ret i1 %tobool4
}
; CHECK-LABEL: test18
; CHECK: if.end:
; CHECK-NEXT: %[[x:.*]] = phi i1
; CHECK-DAG: [ %cmp, %if.then ]
; CHECK-DAG: [ %cmp2, %if.then2 ]
; CHECK-DAG: [ %cmp3, %if.then3 ]
; CHECK-NEXT: zext i1 %[[x]] to i8
; The phi is confusing - both add instructions are used by it, but
; not on their respective unconditional arcs. It should not be
; optimized.
define void @test_pr30292(i1 %cond, i1 %cond2, i32 %a, i32 %b) {
entry:
%add1 = add i32 %a, 1
br label %succ
one:
br i1 %cond, label %two, label %succ
two:
call void @g()
%add2 = add i32 %a, 1
br label %succ
succ:
%p = phi i32 [ 0, %entry ], [ %add1, %one ], [ %add2, %two ]
br label %one
}
declare void @g()
; CHECK-LABEL: test_pr30292
; CHECK: phi i32 [ 0, %entry ], [ %add1, %succ ], [ %add2, %two ]
define zeroext i1 @test_pr30244(i1 zeroext %flag, i1 zeroext %flag2, i32 %blksA, i32 %blksB, i32 %nblks) {
entry:
%p = alloca i8
br i1 %flag, label %if.then, label %if.else
if.then:
%cmp = icmp uge i32 %blksA, %nblks
%frombool1 = zext i1 %cmp to i8
store i8 %frombool1, i8* %p
br label %if.end
if.else:
br i1 %flag2, label %if.then2, label %if.end
if.then2:
%add = add i32 %nblks, %blksB
%cmp2 = icmp ule i32 %add, %blksA
%frombool3 = zext i1 %cmp2 to i8
store i8 %frombool3, i8* %p
br label %if.end
if.end:
ret i1 true
}
; CHECK-LABEL: @test_pr30244
; CHECK: store
; CHECK-NOT: store
define i32 @test_pr30373a(i1 zeroext %flag, i32 %x, i32 %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%x0 = call i32 @foo(i32 %x, i32 0) nounwind readnone
%y0 = call i32 @foo(i32 %x, i32 1) nounwind readnone
%z0 = lshr i32 %y0, 8
br label %if.end
if.else:
%x1 = call i32 @foo(i32 %y, i32 0) nounwind readnone
%y1 = call i32 @foo(i32 %y, i32 1) nounwind readnone
%z1 = lshr exact i32 %y1, 8
br label %if.end
if.end:
%xx = phi i32 [ %x0, %if.then ], [ %x1, %if.else ]
%yy = phi i32 [ %z0, %if.then ], [ %z1, %if.else ]
%ret = add i32 %xx, %yy
ret i32 %ret
}
; CHECK-LABEL: test_pr30373a
; CHECK: lshr
; CHECK-NOT: exact
; CHECK: }
define i32 @test_pr30373b(i1 zeroext %flag, i32 %x, i32 %y) {
entry:
br i1 %flag, label %if.then, label %if.else
if.then:
%x0 = call i32 @foo(i32 %x, i32 0) nounwind readnone
%y0 = call i32 @foo(i32 %x, i32 1) nounwind readnone
%z0 = lshr exact i32 %y0, 8
br label %if.end
if.else:
%x1 = call i32 @foo(i32 %y, i32 0) nounwind readnone
%y1 = call i32 @foo(i32 %y, i32 1) nounwind readnone
%z1 = lshr i32 %y1, 8
br label %if.end
if.end:
%xx = phi i32 [ %x0, %if.then ], [ %x1, %if.else ]
%yy = phi i32 [ %z0, %if.then ], [ %z1, %if.else ]
%ret = add i32 %xx, %yy
ret i32 %ret
}
; CHECK-LABEL: test_pr30373b
; CHECK: lshr
; CHECK-NOT: exact
; CHECK: }
; CHECK: !0 = !{!1, !1, i64 0}
; CHECK: !1 = !{!"float", !2}
; CHECK: !2 = !{!"an example type tree"}