Bug 31582 - iOS -O=float32 fails for some operations on ARM7
Summary: iOS -O=float32 fails for some operations on ARM7
Alias: None
Product: iOS
Classification: Xamarin
Component: Mono runtime / AOT compiler ()
Version: XI 8.13 (C6 early alphas)
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Rodrigo Kumpera
Depends on:
Reported: 2015-07-02 12:30 UTC by Icer addis
Modified: 2015-07-03 14:44 UTC (History)
5 users (show)

Is this bug a regression?: ---
Last known good build:

Attached example project (10.42 KB, application/zip)
2015-07-02 12:30 UTC, Icer addis

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Description Icer addis 2015-07-02 12:30:10 UTC
Created attachment 11823 [details]
Attached example project

Specifically the pseudo instruction: r4_conv_to_u8 when building for ARM7.

Here is example code:

       struct Vector2 {public float x,y;}
        static ulong Test_r4_conv_to_u8(Vector2 size)
            return ((ulong)size.y)<<32 
                | (ulong)size.x<<16; 


I think the conversion is the problem, not the struct value.

The opcode is missing from ARM7:

But it is present here for ARM64:

And there is this case block which may be relevant:

I suggest testing all instructions because there may be more lurking...
Comment 2 Rodrigo Kumpera 2015-07-03 13:31:48 UTC
I'm working on it.
Comment 3 Rodrigo Kumpera 2015-07-03 14:44:13 UTC
Fixed on mono master/5d93b2a292c7609596b9ec0492cd6f80658e3a8f.