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| ; RUN: opt -S -early-cse < %s | FileCheck %s
; RUN: opt < %s -S -basicaa -early-cse-memssa | FileCheck %s
declare void @llvm.experimental.guard(i1,...)
declare void @llvm.assume(i1)
define i32 @test0(i32* %ptr, i1 %cond) {
; We can do store to load forwarding over a guard, since it does not
; clobber memory
; CHECK-LABEL: @test0(
; CHECK-NEXT: store i32 40, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
; CHECK-NEXT: ret i32 40
store i32 40, i32* %ptr
call void(i1,...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
%rval = load i32, i32* %ptr
ret i32 %rval
}
define i32 @test1(i32* %val, i1 %cond) {
; We can CSE loads over a guard, since it does not clobber memory
; CHECK-LABEL: @test1(
; CHECK-NEXT: %val0 = load i32, i32* %val
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
; CHECK-NEXT: ret i32 0
%val0 = load i32, i32* %val
call void(i1,...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
%val1 = load i32, i32* %val
%rval = sub i32 %val0, %val1
ret i32 %rval
}
define i32 @test2() {
; Guards on "true" get removed
; CHECK-LABEL: @test2(
; CHECK-NEXT: ret i32 0
call void(i1, ...) @llvm.experimental.guard(i1 true) [ "deopt"() ]
ret i32 0
}
define i32 @test3(i32 %val) {
; After a guard has executed the condition it was guarding is known to
; be true.
; CHECK-LABEL: @test3(
; CHECK-NEXT: %cond0 = icmp slt i32 %val, 40
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
; CHECK-NEXT: ret i32 -1
%cond0 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
%cond1 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond1) [ "deopt"() ]
%cond2 = icmp slt i32 %val, 40
%rval = sext i1 %cond2 to i32
ret i32 %rval
}
define i32 @test3.unhandled(i32 %val) {
; After a guard has executed the condition it was guarding is known to
; be true.
; CHECK-LABEL: @test3.unhandled(
; CHECK-NEXT: %cond0 = icmp slt i32 %val, 40
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
; CHECK-NEXT: %cond1 = icmp sge i32 %val, 40
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond1) [ "deopt"() ]
; CHECK-NEXT: ret i32 0
; Demonstrates a case we do not yet handle (it is legal to fold %cond2
; to false)
%cond0 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
%cond1 = icmp sge i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond1) [ "deopt"() ]
ret i32 0
}
define i32 @test4(i32 %val, i1 %c) {
; Same as test3, but with some control flow involved.
; CHECK-LABEL: @test4(
; CHECK: entry:
; CHECK-NEXT: %cond0 = icmp slt i32 %val, 40
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond0
; CHECK-NEXT: br label %bb0
; CHECK: bb0:
; CHECK-NEXT: %cond2 = icmp ult i32 %val, 200
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond2
; CHECK-NEXT: br i1 %c, label %left, label %right
; CHECK: left:
; CHECK-NEXT: ret i32 0
; CHECK: right:
; CHECK-NEXT: ret i32 20
entry:
%cond0 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
%cond1 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond1) [ "deopt"() ]
br label %bb0
bb0:
%cond2 = icmp ult i32 %val, 200
call void(i1,...) @llvm.experimental.guard(i1 %cond2) [ "deopt"() ]
br i1 %c, label %left, label %right
left:
%cond3 = icmp ult i32 %val, 200
call void(i1,...) @llvm.experimental.guard(i1 %cond3) [ "deopt"() ]
ret i32 0
right:
ret i32 20
}
define i32 @test5(i32 %val, i1 %c) {
; Same as test4, but the %left block has mutliple predecessors.
; CHECK-LABEL: @test5(
; CHECK: entry:
; CHECK-NEXT: %cond0 = icmp slt i32 %val, 40
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond0
; CHECK-NEXT: br label %bb0
; CHECK: bb0:
; CHECK-NEXT: %cond2 = icmp ult i32 %val, 200
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cond2
; CHECK-NEXT: br i1 %c, label %left, label %right
; CHECK: left:
; CHECK-NEXT: br label %right
; CHECK: right:
; CHECK-NEXT: br label %left
entry:
%cond0 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond0) [ "deopt"() ]
%cond1 = icmp slt i32 %val, 40
call void(i1,...) @llvm.experimental.guard(i1 %cond1) [ "deopt"() ]
br label %bb0
bb0:
%cond2 = icmp ult i32 %val, 200
call void(i1,...) @llvm.experimental.guard(i1 %cond2) [ "deopt"() ]
br i1 %c, label %left, label %right
left:
%cond3 = icmp ult i32 %val, 200
call void(i1,...) @llvm.experimental.guard(i1 %cond3) [ "deopt"() ]
br label %right
right:
br label %left
}
define void @test6(i1 %c, i32* %ptr) {
; Check that we do not DSE over calls to @llvm.experimental.guard.
; Guard intrinsics do _read_ memory, so th call to guard below needs
; to see the store of 500 to %ptr
; CHECK-LABEL: @test6(
; CHECK-NEXT: store i32 500, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %c) [ "deopt"() ]
; CHECK-NEXT: store i32 600, i32* %ptr
store i32 500, i32* %ptr
call void(i1,...) @llvm.experimental.guard(i1 %c) [ "deopt"() ]
store i32 600, i32* %ptr
ret void
}
define void @test07(i32 %a, i32 %b) {
; Check that we are able to remove the guards on the same condition even if the
; condition is not being recalculated.
; CHECK-LABEL: @test07(
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: ret void
%cmp = icmp eq i32 %a, %b
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
ret void
}
define void @test08(i32 %a, i32 %b, i32* %ptr) {
; Check that we deal correctly with stores when removing guards in the same
; block in case when the condition is not recalculated.
; CHECK-LABEL: @test08(
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: store i32 100, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: ret void
%cmp = icmp eq i32 %a, %b
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 200, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
ret void
}
define void @test09(i32 %a, i32 %b, i1 %c, i32* %ptr) {
; Similar to test08, but with more control flow.
; TODO: Can we get rid of the store in the end of entry given that it is
; post-dominated by other stores?
; CHECK-LABEL: @test09(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: store i32 100, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: br i1 %c, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: store i32 500, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: store i32 600, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 200, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
br i1 %c, label %if.true, label %if.false
if.true:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 500, i32* %ptr
br label %merge
if.false:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 600, i32* %ptr
br label %merge
merge:
ret void
}
define void @test10(i32 %a, i32 %b, i1 %c, i32* %ptr) {
; Make sure that non-dominating guards do not cause other guards removal.
; CHECK-LABEL: @test10(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: br i1 %c, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: store i32 100, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: store i32 200, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: store i32 300, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
br i1 %c, label %if.true, label %if.false
if.true:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
br label %merge
if.false:
store i32 200, i32* %ptr
br label %merge
merge:
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
ret void
}
define void @test11(i32 %a, i32 %b, i32* %ptr) {
; Make sure that branching condition is applied to guards.
; CHECK-LABEL: @test11(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: br i1 %cmp, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"() ]
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %if.true, label %if.false
if.true:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
br label %merge
if.false:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
br label %merge
merge:
ret void
}
define void @test12(i32 %a, i32 %b) {
; Check that the assume marks its condition as being true (and thus allows to
; eliminate the dominated guards).
; CHECK-LABEL: @test12(
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: ret void
%cmp = icmp eq i32 %a, %b
call void @llvm.assume(i1 %cmp)
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
ret void
}
define void @test13(i32 %a, i32 %b, i32* %ptr) {
; Check that we deal correctly with stores when removing guards due to assume.
; CHECK-LABEL: @test13(
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: ret void
%cmp = icmp eq i32 %a, %b
call void @llvm.assume(i1 %cmp)
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 200, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
ret void
}
define void @test14(i32 %a, i32 %b, i1 %c, i32* %ptr) {
; Similar to test13, but with more control flow.
; TODO: Can we get rid of the store in the end of entry given that it is
; post-dominated by other stores?
; CHECK-LABEL: @test14(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: br i1 %c, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: store i32 500, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: store i32 600, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
call void @llvm.assume(i1 %cmp)
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 200, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
br i1 %c, label %if.true, label %if.false
if.true:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 500, i32* %ptr
br label %merge
if.false:
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 600, i32* %ptr
br label %merge
merge:
ret void
}
define void @test15(i32 %a, i32 %b, i1 %c, i32* %ptr) {
; Make sure that non-dominating assumes do not cause guards removal.
; CHECK-LABEL: @test15(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: br i1 %c, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: store i32 100, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: store i32 200, i32* %ptr
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: store i32 300, i32* %ptr
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
; CHECK-NEXT: store i32 400, i32* %ptr
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
br i1 %c, label %if.true, label %if.false
if.true:
call void @llvm.assume(i1 %cmp)
store i32 100, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
br label %merge
if.false:
store i32 200, i32* %ptr
br label %merge
merge:
store i32 300, i32* %ptr
call void (i1, ...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
store i32 400, i32* %ptr
ret void
}
define void @test16(i32 %a, i32 %b) {
; Check that we don't bother to do anything with assumes even if we know the
; condition being true.
; CHECK-LABEL: @test16(
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: ret void
%cmp = icmp eq i32 %a, %b
call void @llvm.assume(i1 %cmp)
call void @llvm.assume(i1 %cmp)
ret void
}
define void @test17(i32 %a, i32 %b, i1 %c, i32* %ptr) {
; Check that we don't bother to do anything with assumes even if we know the
; condition being true or false (includes come control flow).
; CHECK-LABEL: @test17(
; CHECK: entry:
; CHECK-NEXT: %cmp = icmp eq i32 %a, %b
; CHECK-NEXT: br i1 %c, label %if.true, label %if.false
; CHECK: if.true:
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: br label %merge
; CHECK: if.false:
; CHECK-NEXT: call void @llvm.assume(i1 %cmp)
; CHECK-NEXT: br label %merge
; CHECK: merge:
; CHECK-NEXT: ret void
entry:
%cmp = icmp eq i32 %a, %b
br i1 %c, label %if.true, label %if.false
if.true:
call void @llvm.assume(i1 %cmp)
br label %merge
if.false:
call void @llvm.assume(i1 %cmp)
br label %merge
merge:
ret void
}
define void @test18(i1 %c) {
; Check that we don't bother to do anything with assumes even if we know the
; condition being true and not being an instruction.
; CHECK-LABEL: @test18(
; CHECK-NEXT: call void @llvm.assume(i1 %c)
; CHECK-NEXT: call void @llvm.assume(i1 %c)
; CHECK-NEXT: ret void
call void @llvm.assume(i1 %c)
call void @llvm.assume(i1 %c)
ret void
}
|