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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
// The original bug for this test was an assertion after the following sequence of events:
// - Assertion propagation constant propagated away the ldlocs, or, and shl in the IL at label "expr"
// - After constant propagation, the resulting expression--`(mod tmp0 cns)`--was remorphed, which
// replaced the modulus with `(sub tmp0 (mul (div tmp0 cns) cns))` and unset the "exception" flag.
// Critically, this transformation added a new use of `tmp0` without updating the ref count for `tmp0`.
// - After morphing, the resulting expression was both unsused and side-effect-free, and was removed
// - While removing the lclVar ref count for `tmp0` fell to `0`
// - Later, liveness found a reference to `tmp0` despite the `0` lclVar count and asserted.
//
// The fix was to bump lclVar ref counts after remorphing but before attempting to remove the expression.
.assembly extern mscorlib{}
.assembly ILGEN_MODULE{}
.class ILGEN_CLASS
{
.method static char ILGEN_METHOD(bool, char, int16, int32)
{
.maxstack 65535
.locals init (int32, int16, int64, int16, unsigned int8, float32, unsigned int8)
ldc.i8 0x80BBE1AB
ldc.i8 0x866D9EF3
or
ldarg 0x1
shl
ldc.i8 0xC09C2177
sub.ovf.un
conv.ovf.u8.un
ldc.i8 0x82B1C678
or
ldc.r8 -0.000000
ldloc 0x5
ckfinite
ldloc 0x5
neg
neg
add
add
ldc.r8 0.000000
clt
stloc.s 0x4
ldc.i8 0xACB4FC40
expr:
ldloc.s 0x3
ldloc.s 0x0
or
shl
rem
conv.ovf.i8
ldloc.s 0x4
conv.ovf.u
neg
brtrue IL_0089
ldarg 0x0
conv.ovf.i8
conv.i8
ldc.i8 0x2ECADED8
ldloc 0x2
shr
clt
pop
ldloc.s 0x1
conv.ovf.u1.un
conv.ovf.u.un
starg 0x0
IL_0089:
ldarg.s 0x3
conv.u8
bgt IL_0094
ldloc.s 0x5
pop
IL_0094:
ldc.r8 0.000000
neg
conv.i
ldloc 0x5
ckfinite
ldc.i8 0x8BD98F2C
conv.r4
ckfinite
clt
pop
neg
ret
}
.method static int32 Main()
{
.entrypoint
.try
{
ldc.i4 0
dup
dup
dup
call char ILGEN_CLASS::ILGEN_METHOD(bool, char, int16, int32)
pop
leave.s done
}
catch [mscorlib]System.Exception
{
leave.s done
}
done:
ldc.i4 100
ret
}
}
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