Comments on: Never rely on tail recursion elimination http://ripper234.com/p/never-rely-on-tail-recursion-elimination/ Stuff Ron Gross Finds Interesting Fri, 27 Jan 2012 03:20:29 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Tomer Gabelhttp://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1270 Tomer Gabel Fri, 06 Feb 2009 12:52:01 +0000 http://ripper234.com/?p=925#comment-1270 In that case, I'm (badly) surprised. I'll try to do some more research on the subject. In that case, I’m (badly) surprised. I’ll try to do some more research on the subject.

]]> By: ripper234http://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1267 ripper234 Fri, 06 Feb 2009 06:46:33 +0000 http://ripper234.com/?p=925#comment-1267 Yes you can. Yes you can.

]]> By: Tomer Gabelhttp://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1261 Tomer Gabel Thu, 05 Feb 2009 17:27:09 +0000 http://ripper234.com/?p=925#comment-1261 Can I assume you've compiled for RELEASE? Can I assume you’ve compiled for RELEASE?

]]> By: ripper234http://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1260 ripper234 Thu, 05 Feb 2009 17:25:24 +0000 http://ripper234.com/?p=925#comment-1260 I went to said location, viewed it with reflector, and this is what it shows. I don't really have the will to open IDA now, but running the example proves my point. I went to said location, viewed it with reflector, and this is what it shows.
I don’t really have the will to open IDA now, but running the example proves my point.

]]> By: Tomer Gabelhttp://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1259 Tomer Gabel Thu, 05 Feb 2009 17:13:50 +0000 http://ripper234.com/?p=925#comment-1259 That's not an ngen image - I'm talking native code, here. Try C:\Windows\assembly\NativeImages_v2.0.50727_32, I think that's where ngen'd assemblies go. That’s not an ngen image – I’m talking native code, here. Try C:\Windows\assembly\NativeImages_v2.0.50727_32, I think that’s where ngen’d assemblies go.

]]> By: ripper234http://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1255 ripper234 Thu, 05 Feb 2009 08:56:42 +0000 http://ripper234.com/?p=925#comment-1255 NGen does't help. <pre> .method private hidebysig static void Foo(int32 i) cil managed { .maxstack 8 L_0000: ldarg.0 L_0001: ldc.i4 0xf4240 L_0006: bne.un.s L_0009 L_0008: ret L_0009: ldarg.0 L_000a: ldc.i4.s 100 L_000c: rem L_000d: brtrue.s L_0015 L_000f: ldarg.0 L_0010: call void [mscorlib]System.Console::WriteLine(int32) L_0015: ldarg.0 L_0016: ldc.i4.1 L_0017: add L_0018: call void StackOverflow.Program::Foo(int32) L_001d: ret } </pre> NGen does’t help.

.method private hidebysig static void Foo(int32 i) cil managed
{
    .maxstack 8
    L_0000: ldarg.0
    L_0001: ldc.i4 0xf4240
    L_0006: bne.un.s L_0009
    L_0008: ret
    L_0009: ldarg.0
    L_000a: ldc.i4.s 100
    L_000c: rem
    L_000d: brtrue.s L_0015
    L_000f: ldarg.0
    L_0010: call void [mscorlib]System.Console::WriteLine(int32)
    L_0015: ldarg.0
    L_0016: ldc.i4.1
    L_0017: add
    L_0018: call void StackOverflow.Program::Foo(int32)
    L_001d: ret
}
]]> By: ripper234http://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1226 ripper234 Tue, 03 Feb 2009 09:11:59 +0000 http://ripper234.com/?p=925#comment-1226 I've read somewhere that NGen doesn't help. Will verify. The JIT obviously didn't optimize it away because it did throw a StackOverflowException. I’ve read somewhere that NGen doesn’t help. Will verify. The JIT obviously didn’t optimize it away because it did throw a StackOverflowException.

]]> By: Tomer Gabelhttp://ripper234.com/p/never-rely-on-tail-recursion-elimination/comment-page-1/#comment-1213 Tomer Gabel Mon, 02 Feb 2009 18:38:37 +0000 http://ripper234.com/?p=925#comment-1213 Inconclusive: try NGen'ing the compiled assembly and check the generated native code. CSC performs almost no optimizations; nearly everything is done in the JIT. Inconclusive: try NGen’ing the compiled assembly and check the generated native code. CSC performs almost no optimizations; nearly everything is done in the JIT.

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