; RUN: opt -passes='loop(simple-loop-unswitch),verify<loops>' -S < %s | FileCheck %s
; RUN: opt -verify-memoryssa -passes='loop-mssa(simple-loop-unswitch),verify<loops>' -S < %s | FileCheck %s
define i32 @test(ptr %A, i1 %C) {
entry:
br label %no_exit
no_exit: ; preds = %no_exit.backedge, %entry
%i.0.0 = phi i32 [ 0, %entry ], [ %i.0.0.be, %no_exit.backedge ] ; <i32> [#uses=3]
%gep.upgrd.1 = zext i32 %i.0.0 to i64 ; <i64> [#uses=1]
%tmp.7 = getelementptr i32, ptr %A, i64 %gep.upgrd.1 ; <ptr> [#uses=4]
%tmp.13 = load i32, ptr %tmp.7 ; <i32> [#uses=2]
%tmp.14 = add i32 %tmp.13, 1 ; <i32> [#uses=1]
store i32 %tmp.14, ptr %tmp.7
br i1 %C, label %then, label %endif
then: ; preds = %no_exit
%tmp.29 = load i32, ptr %tmp.7 ; <i32> [#uses=1]
%tmp.30 = add i32 %tmp.29, 2 ; <i32> [#uses=1]
store i32 %tmp.30, ptr %tmp.7
%inc9 = add i32 %i.0.0, 1 ; <i32> [#uses=2]
%tmp.112 = icmp ult i32 %inc9, 100000 ; <i1> [#uses=1]
br i1 %tmp.112, label %no_exit.backedge, label %return
no_exit.backedge: ; preds = %endif, %then
%i.0.0.be = phi i32 [ %inc9, %then ], [ %inc, %endif ] ; <i32> [#uses=1]
br label %no_exit
endif: ; preds = %no_exit
%inc = add i32 %i.0.0, 1 ; <i32> [#uses=2]
%tmp.1 = icmp ult i32 %inc, 100000 ; <i1> [#uses=1]
br i1 %tmp.1, label %no_exit.backedge, label %return
return: ; preds = %endif, %then
ret i32 %tmp.13
}
; This simple test would normally unswitch, but should be inhibited by the presence of
; the noduplicate call.
; CHECK-LABEL: @test2(
define i32 @test2(ptr %var) {
%mem = alloca i32
store i32 2, ptr %mem
%c = load i32, ptr %mem
br label %loop_begin
loop_begin:
%var_val = load i32, ptr %var
switch i32 %c, label %default [
i32 1, label %inc
i32 2, label %dec
]
inc:
call void @incf() noreturn nounwind
br label %loop_begin
dec:
; CHECK: call void @decf()
; CHECK-NOT: call void @decf()
call void @decf() noreturn nounwind noduplicate
br label %loop_begin
default:
br label %loop_exit
loop_exit:
ret i32 0
; CHECK: }
}
; This simple test would normally unswitch, but should be inhibited by the presence of
; the convergent call that is not control-dependent on the unswitch condition.
; CHECK-LABEL: @test3(
define i32 @test3(ptr %var) {
%mem = alloca i32
store i32 2, ptr %mem
%c = load i32, ptr %mem
br label %loop_begin
loop_begin:
%var_val = load i32, ptr %var
; CHECK: call void @conv()
; CHECK-NOT: call void @conv()
call void @conv() convergent
switch i32 %c, label %default [
i32 1, label %inc
i32 2, label %dec
]
inc:
call void @incf() noreturn nounwind
br label %loop_begin
dec:
call void @decf() noreturn nounwind
br label %loop_begin
default:
br label %loop_exit
loop_exit:
ret i32 0
; CHECK: }
}
; Make sure we don't unswitch, as we can not find an input value %a
; that will effectively unswitch 0 or 3 out of the loop.
;
; CHECK: define void @and_or_i2_as_switch_input(i2
; CHECK: entry:
; This is an indication that the loop has NOT been unswitched.
; CHECK-NOT: icmp
; CHECK: br
define void @and_or_i2_as_switch_input(i2 %a) {
entry:
br label %for.body
for.body:
%i = phi i2 [ 0, %entry ], [ %inc, %for.inc ]
%and = and i2 %a, %i
%or = or i2 %and, %i
switch i2 %or, label %sw.default [
i2 0, label %sw.bb
i2 3, label %sw.bb1
]
sw.bb:
br label %sw.epilog
sw.bb1:
br label %sw.epilog
sw.default:
br label %sw.epilog
sw.epilog:
br label %for.inc
for.inc:
%inc = add nsw i2 %i, 1
%cmp = icmp slt i2 %inc, 3
br i1 %cmp, label %for.body, label %for.end
for.end:
ret void
}
; Make sure we don't unswitch, as we can not find an input value %a
; that will effectively unswitch true/false out of the loop.
;
; CHECK: define void @and_or_i1_as_branch_input(i1
; CHECK: entry:
; This is an indication that the loop has NOT been unswitched.
; CHECK-NOT: icmp
; CHECK: br
define void @and_or_i1_as_branch_input(i1 %a) {
entry:
br label %for.body
for.body:
%i = phi i1 [ 0, %entry ], [ %inc, %for.inc ]
%and = and i1 %a, %i
%or = or i1 %and, %i
br i1 %or, label %sw.bb, label %sw.bb1
sw.bb:
br label %sw.epilog
sw.bb1:
br label %sw.epilog
sw.epilog:
br label %for.inc
for.inc:
%inc = add nsw i1 %i, 1
%cmp = icmp slt i1 %inc, 1
br i1 %cmp, label %for.body, label %for.end
for.end:
ret void
}
declare void @incf() noreturn
declare void @decf() noreturn
declare void @conv() convergent
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