180 lines
4.1 KiB
LLVM
180 lines
4.1 KiB
LLVM
; RUN: opt %s -S -simplifycfg | FileCheck %s
|
|
declare void @foo(i32)
|
|
|
|
define void @test(i1 %a) {
|
|
; CHECK-LABEL: @test
|
|
; CHECK: br i1 [[IGNORE:%.*]], label %true, label %false
|
|
switch i1 %a, label %default [i1 1, label %true
|
|
i1 0, label %false]
|
|
true:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
false:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
default:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
}
|
|
|
|
define void @test2(i2 %a) {
|
|
; CHECK-LABEL: @test2
|
|
switch i2 %a, label %default [i2 0, label %case0
|
|
i2 1, label %case1
|
|
i2 2, label %case2
|
|
i2 3, label %case3]
|
|
case0:
|
|
call void @foo(i32 0)
|
|
ret void
|
|
case1:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
case2:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
case3:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
default:
|
|
; CHECK-LABEL: default1:
|
|
; CHECK-NEXT: unreachable
|
|
call void @foo(i32 4)
|
|
ret void
|
|
}
|
|
|
|
; This one is a negative test - we know the value of the default,
|
|
; but that's about it
|
|
define void @test3(i2 %a) {
|
|
; CHECK-LABEL: @test3
|
|
switch i2 %a, label %default [i2 0, label %case0
|
|
i2 1, label %case1
|
|
i2 2, label %case2]
|
|
|
|
case0:
|
|
call void @foo(i32 0)
|
|
ret void
|
|
case1:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
case2:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
default:
|
|
; CHECK-LABEL: default:
|
|
; CHECK-NEXT: call void @foo
|
|
call void @foo(i32 0)
|
|
ret void
|
|
}
|
|
|
|
; Negative test - check for possible overflow when computing
|
|
; number of possible cases.
|
|
define void @test4(i128 %a) {
|
|
; CHECK-LABEL: @test4
|
|
switch i128 %a, label %default [i128 0, label %case0
|
|
i128 1, label %case1]
|
|
|
|
case0:
|
|
call void @foo(i32 0)
|
|
ret void
|
|
case1:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
default:
|
|
; CHECK-LABEL: default:
|
|
; CHECK-NEXT: call void @foo
|
|
call void @foo(i32 0)
|
|
ret void
|
|
}
|
|
|
|
; All but one bit known zero
|
|
define void @test5(i8 %a) {
|
|
; CHECK-LABEL: @test5
|
|
; CHECK: br i1 [[IGNORE:%.*]], label %true, label %false
|
|
%cmp = icmp ult i8 %a, 2
|
|
call void @llvm.assume(i1 %cmp)
|
|
switch i8 %a, label %default [i8 1, label %true
|
|
i8 0, label %false]
|
|
true:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
false:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
default:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
}
|
|
|
|
;; All but one bit known one
|
|
define void @test6(i8 %a) {
|
|
; CHECK-LABEL: @test6
|
|
; CHECK: @llvm.assume
|
|
; CHECK: br i1 [[IGNORE:%.*]], label %true, label %false
|
|
%and = and i8 %a, 254
|
|
%cmp = icmp eq i8 %and, 254
|
|
call void @llvm.assume(i1 %cmp)
|
|
switch i8 %a, label %default [i8 255, label %true
|
|
i8 254, label %false]
|
|
true:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
false:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
default:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
}
|
|
|
|
; Check that we can eliminate both dead cases and dead defaults
|
|
; within a single run of simplify-cfg
|
|
define void @test7(i8 %a) {
|
|
; CHECK-LABEL: @test7
|
|
; CHECK: @llvm.assume
|
|
; CHECK: br i1 [[IGNORE:%.*]], label %true, label %false
|
|
%and = and i8 %a, 254
|
|
%cmp = icmp eq i8 %and, 254
|
|
call void @llvm.assume(i1 %cmp)
|
|
switch i8 %a, label %default [i8 255, label %true
|
|
i8 254, label %false
|
|
i8 0, label %also_dead]
|
|
true:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
false:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
also_dead:
|
|
call void @foo(i32 5)
|
|
ret void
|
|
default:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
}
|
|
|
|
;; All but one bit known undef
|
|
;; Note: This is currently testing an optimization which doesn't trigger. The
|
|
;; case this is protecting against is that a bit could be assumed both zero
|
|
;; *or* one given we know it's undef. ValueTracking doesn't do this today,
|
|
;; but it doesn't hurt to confirm.
|
|
define void @test8(i8 %a) {
|
|
; CHECK-LABEL: @test8(
|
|
; CHECK: switch i8
|
|
%and = and i8 %a, 254
|
|
%cmp = icmp eq i8 %and, undef
|
|
call void @llvm.assume(i1 %cmp)
|
|
switch i8 %a, label %default [i8 255, label %true
|
|
i8 254, label %false]
|
|
true:
|
|
call void @foo(i32 1)
|
|
ret void
|
|
false:
|
|
call void @foo(i32 3)
|
|
ret void
|
|
default:
|
|
call void @foo(i32 2)
|
|
ret void
|
|
}
|
|
|
|
declare void @llvm.assume(i1)
|