[Mono-dev] Arm9 NS9215 floating point troubles
I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
afaik) and I'm having trouble with floats when executing code.
I
thought I had correctly specified soft-float and indeed mono tells me so
~
# /usr/local/bin/mono -V
Mono JIT compiler version 2.6.4 (tarball
Wed Jun 16 14:55:33 MDT 2010)
Copyright (C) 2002-2010 Novell, Inc and
Contributors. www.mono-project.com
TLS: normal
GC: Included Boehm (with
typed GC and Parallel Mark)
SIGSEGV: normal
Notifications:
epoll
Architecture: arm,soft-float
Disabled: none
~ #
However the following code produces
grossly wrong results
using System;
public class FloatTest
{
static public void Main()
{
Console.WriteLine("0.0f literal is " + 0.0f);
Console.WriteLine("1.0f literal is " + 1.0f);
Console.WriteLine("12.3f literal is " + 12.3f);
Console.WriteLine("32f
literal is " + 32f);
Console.WriteLine("1024f
literal is " + 1024f);
Console.WriteLine("32768f
literal is " + 32768f);
}
}
Here are the results
~
# /usr/local/bin/mono FloatTest.exe
0.0f literal is 0
1.0f
literal is 5.299809E-315
12.3f literal is -1.491669E-154
32f
literal is 5.325712E-315
1024f literal is 5.351615E-315
32768f
literal is 5.377519E-315
my configure command is
./configure
--host=arm-linux --with-tls=pthread --with-moonlight=no
--with-mcs-docs=no
summary from running config is
mcs source: $(top_srcdir)/mcs
olive source:
GC: included
GLIB:
system
TLS: pthread
SIGALTSTACK: yes
Engine: Building and using the JIT
2.0 Profile: yes
Moon Profile: no
4.0 Alpha: no
MonoTouch: no
JNI support: IKVM
Native
libgdiplus: assumed to be installed
zlib: system zlib
oprofile: no
BigArrays: no
DTrace: no
Parallel Mark:
yes
LLVM Back End: no
My CFLAGS and CPPFLAGS environment variables are
both
-DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
Any insight
would be greatly appreciated, I've looked at some of the code in the
mono/mini directory but cannot make sense of how float values are
getting generated.
TIA
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
On 17.06.2010 18:07, Trevor Ackerman wrote: > I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu > afaik) and I'm having trouble with floats when executing code. ... > My CFLAGS and CPPFLAGS environment variables are > both > -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1 -DNO_UNALIGNED_ACCESS is probably needed as well. Robert ___ Mono-devel-list mailing list Mono-devel-list@lists.ximian.com http://lists.ximian.com/mailman/listinfo/mono-devel-list
Re: [Mono-dev] Arm9 NS9215 floating point troubles
Good suggestion but that did not change the results. --- On Thu, 6/17/10, Robert Jordan wrote: From: Robert Jordan Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles To: mono-devel-list@lists.ximian.com Date: Thursday, June 17, 2010, 10:53 AM On 17.06.2010 18:07, Trevor Ackerman wrote: > I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu > afaik) and I'm having trouble with floats when executing code. ... > My CFLAGS and CPPFLAGS environment variables are > both > -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1 -DNO_UNALIGNED_ACCESS is probably needed as well. Robert ___ Mono-devel-list mailing list Mono-devel-list@lists.ximian.com http://lists.ximian.com/mailman/listinfo/mono-devel-list ___ Mono-devel-list mailing list Mono-devel-list@lists.ximian.com http://lists.ximian.com/mailman/listinfo/mono-devel-list
Re: [Mono-dev] Arm9 NS9215 floating point troubles
Trevor,
I tested your testcase on a:
Processor : ARMv7 Processor rev 0 (v7l)
Features: swp half thumb fastmult vfp edsp thumbee vfpv3 vfpv3d16
I tested:
Mono JIT compiler version 2.4.2.3 (Debian 2.4.2.3+dfsg-2)
Architecture: armel,soft-float
Mono JIT compiler version 2.7 (/trunk/mono r158961 Tue Jun 15 17:26:35 EDT 2010)
Architecture: armel,vfp
Mono JIT compiler version 2.7 (/trunk/mono r158961 Thu Jun 17 13:58:00 EDT 2010)
Architecture: armel,soft-float
and all 3 produce the correct results. I dont have a 2.6.4 build handy, but
nothing really significant in this regard has changed. Could you try trunk?
It might be something else with your board as well.
-g
On 2010-06-17, at 12:07 PM, Trevor Ackerman wrote:
> I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu afaik)
> and I'm having trouble with floats when executing code.
>
> I thought I had correctly specified soft-float and indeed mono tells me so
>
> ~ # /usr/local/bin/mono -V
> Mono JIT compiler version 2.6.4 (tarball Wed Jun 16 14:55:33 MDT 2010)
> Copyright (C) 2002-2010 Novell, Inc and Contributors. www.mono-project.com
> TLS: normal
> GC:Included Boehm (with typed GC and Parallel Mark)
> SIGSEGV: normal
> Notifications: epoll
> Architecture: arm,soft-float
> Disabled: none
> ~ #
>
> However the following code produces grossly wrong results
>
> using System;
>
> public class FloatTest
> {
> static public void Main()
> {
> Console.WriteLine("0.0f literal is " + 0.0f);
> Console.WriteLine("1.0f literal is " + 1.0f);
> Console.WriteLine("12.3f literal is " + 12.3f);
> Console.WriteLine("32f literal is " + 32f);
> Console.WriteLine("1024f literal is " + 1024f);
> Console.WriteLine("32768f literal is " + 32768f);
> }
> }
>
> Here are the results
>
> ~ # /usr/local/bin/mono FloatTest.exe
> 0.0f literal is 0
> 1.0f literal is 5.299809E-315
> 12.3f literal is -1.491669E-154
> 32f literal is 5.325712E-315
> 1024f literal is 5.351615E-315
> 32768f literal is 5.377519E-315
>
> my configure command is
> ./configure --host=arm-linux --with-tls=pthread --with-moonlight=no
> --with-mcs-docs=no
>
> summary from running config is
>
> mcs source:$(top_srcdir)/mcs
> olive source:
>
> GC:included
> GLIB: system
> TLS: pthread
> SIGALTSTACK: yes
> Engine:Building and using the JIT
> 2.0 Profile: yes
> Moon Profile: no
> 4.0 Alpha: no
> MonoTouch: no
> JNI support: IKVM Native
> libgdiplus:assumed to be installed
> zlib: system zlib
> oprofile: no
> BigArrays: no
> DTrace:no
> Parallel Mark: yes
> LLVM Back End: no
>
> My CFLAGS and CPPFLAGS environment variables are both
> -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
>
> Any insight would be greatly appreciated, I've looked at some of the code in
> the mono/mini directory but cannot make sense of how float values are getting
> generated.
>
> TIA
>
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
I have more to report.
I wrote a quick native C program to print out the bytes of a float and double
variable that were assigned the literal value 1.0f.
Then in the mono 2.6.4 routine mono_method_to_ir in source code file
mono/mini/method_to_ir.c I dumped out the bytes of ip (instruction pointer)
used for the double value in the case for CEE_LDC_R8.
I discovered that the bytes in the double value used on mono had the high and
low 32 bits swapped compared to those produced by the native C program. I
hacked the routine decompose_soft_float to swap the high and low words and now
I have no troubles and the basic-float regression test passes 100%.
Although this happens to work, I have a hard time believing that this is the
correct solution to my problem. I feel that others are probably using ARM9
without
floating point issues and that I am probably missing something in how I built
mono for my platform. If anyone can shed some light on what I did wrong with
building mono that'd be great. Of course if this is the correct action to take
please let me know that too and how I may contribute the change back to the
trunk (assuming that the trunk doesn't work which I haven't had time to test
yet).
In the meantime here's my hack to decompose_soft_float in method-to-ir.c
5073 case OP_R8CONST: {
5074 unsigned char *ucp = (unsigned char *) ins->inst_p0;
5075 unsigned char rawval[8];
5076 printf("decompose_soft_float OP_R8CONST\n");
5077 rawval[0] =
ucp[4];
5078 rawval[1] = ucp[5];
5079 rawval[2] = ucp[6];
5080 rawval[3] = ucp[7];
5081 rawval[4] = ucp[0];
5082 rawval[5] = ucp[1];
5083 rawval[6] = ucp[2];
5084 rawval[7] = ucp[3];
5085 DVal d;
5086
// d.vald = *(double*)ins->inst_p0;
5087 d.vald = *(double*)rawval;
5088 MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
5089 break;
5090 }
--- On Thu, 6/17/10, Trevor Ackerman wrote:
From: Trevor Ackerman
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: mono-devel-list@lists.ximian.com
Date: Thursday, June 17, 2010, 11:31 AM
Good suggestion but that did not change the results.
--- On Thu, 6/17/10, Robert Jordan wrote:
From: Robert Jordan
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: mono-devel-list@lists.ximian.com
Date: Thursday, June 17, 2010, 10:53 AM
On 17.06.2010 18:07, Trevor Ackerman wrote:
> I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
> afaik) and I'm having trouble with floats when executing
code.
...
> My CFLAGS and CPPFLAGS environment variables are
> both
> -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
-DNO_UNALIGNED_ACCESS is probably needed as
well.
Robert
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
Is your system armeb or armel?
It could be a endian bug in our softfloat impl somewhere.
-g
On 2010-06-17, at 7:54 PM, Trevor Ackerman wrote:
> I have more to report.
>
> I wrote a quick native C program to print out the bytes of a float and double
> variable that were assigned the literal value 1.0f.
>
> Then in the mono 2.6.4 routine mono_method_to_ir in source code file
> mono/mini/method_to_ir.c I dumped out the bytes of ip (instruction pointer)
> used for the double value in the case for CEE_LDC_R8.
>
> I discovered that the bytes in the double value used on mono had the high and
> low 32 bits swapped compared to those produced by the native C program. I
> hacked the routine decompose_soft_float to swap the high and low words and
> now I have no troubles and the basic-float regression test passes 100%.
>
> Although this happens to work, I have a hard time believing that this is the
> correct solution to my problem. I feel that others are probably using ARM9
> without floating point issues and that I am probably missing something in how
> I built mono for my platform. If anyone can shed some light on what I did
> wrong with building mono that'd be great. Of course if this is the correct
> action to take please let me know that too and how I may contribute the
> change back to the trunk (assuming that the trunk doesn't work which I
> haven't had time to test yet).
>
> In the meantime here's my hack to decompose_soft_float in method-to-ir.c
>
>
> 5073 case OP_R8CONST: {
> 5074 unsigned char *ucp = (unsigned char *) ins->inst_p0;
> 5075 unsigned char rawval[8];
> 5076 printf("decompose_soft_float OP_R8CONST\n");
> 5077 rawval[0] = ucp[4];
> 5078 rawval[1] = ucp[5];
> 5079 rawval[2] = ucp[6];
> 5080 rawval[3] = ucp[7];
> 5081 rawval[4] = ucp[0];
> 5082 rawval[5] = ucp[1];
> 5083 rawval[6] = ucp[2];
> 5084 rawval[7] = ucp[3];
> 5085 DVal d;
> 5086 // d.vald = *(double*)ins->inst_p0;
> 5087 d.vald = *(double*)rawval;
> 5088 MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
> 5089 break;
> 5090 }
>
> --- On Thu, 6/17/10, Trevor Ackerman wrote:
>
> From: Trevor Ackerman
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 11:31 AM
>
> Good suggestion but that did not change the results.
>
> --- On Thu, 6/17/10, Robert Jordan wrote:
>
> From: Robert Jordan
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 10:53 AM
>
> On 17.06.2010 18:07, Trevor Ackerman wrote:
> > I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
> > afaik) and I'm having trouble with floats when executing code.
>
> ...
>
> > My CFLAGS and CPPFLAGS environment variables are
> > both
> > -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
>
> -DNO_UNALIGNED_ACCESS is probably needed as well.
>
> Robert
>
> ___
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>
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
I believe it is armel, here's what 'file' reports for a natively compiled C
program.
hello_world_c: ELF 32-bit LSB executable, ARM, version 1, dynamically linked
(uses shared libs), not stripped.
Let me know if you still believe it is a bug and how I may contribute a
solution, whether the example change I posted is appropriate or not.
Thanks
--- On Thu, 6/17/10, Geoff Norton wrote:
From: Geoff Norton
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: "Trevor Ackerman"
Cc: mono-devel-list@lists.ximian.com
Date: Thursday, June 17, 2010, 9:54 PM
Is your system armeb or armel?
It could be a endian bug in our softfloat impl somewhere.
-g
On 2010-06-17, at 7:54 PM, Trevor Ackerman wrote:
I have more to report.
I wrote a quick native C program to print out the bytes of a float and double
variable that were assigned the literal value 1.0f.
Then in the mono 2.6.4 routine mono_method_to_ir in source code file
mono/mini/method_to_ir.c I dumped out the bytes of ip (instruction pointer)
used for the double value in the case for CEE_LDC_R8.
I discovered that the bytes in the double value used on mono had the high and
low 32 bits swapped compared to those produced by the native C program. I
hacked the routine decompose_soft_float to swap the high and low words and now
I have no troubles and the basic-float regression test passes 100%.
Although this happens to work, I have a hard time believing that this is the
correct solution to my problem. I feel that others are probably using ARM9
without
floating point issues and that I am probably missing something in how I built
mono for my platform. If anyone can shed some light on what I did wrong with
building mono that'd be great. Of course if this is the correct action to take
please let me know that too and how I may contribute the change back to the
trunk (assuming that the trunk doesn't work which I haven't had time to test
yet).
In the meantime here's my hack to decompose_soft_float in method-to-ir.c
5073 case OP_R8CONST: {
5074 unsigned char *ucp = (unsigned char *) ins->inst_p0;
5075 unsigned char
rawval[8];
5076 printf("decompose_soft_float OP_R8CONST\n");
5077 rawval[0] =
ucp[4];
5078 rawval[1] = ucp[5];
5079 rawval[2] = ucp[6];
5080 rawval[3] = ucp[7];
5081 rawval[4] = ucp[0];
5082 rawval[5] = ucp[1];
5083 rawval[6] = ucp[2];
5084 rawval[7] = ucp[3];
5085 DVal d;
5086
// d.vald = *(double*)ins->inst_p0;
5087 d.vald = *(double*)rawval;
5088 MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
5089 break;
5090 }
--- On Thu, 6/17/10, Trevor Ackerman wrote:
From: Trevor Ackerman
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: mono-devel-list@lists.ximian.com
Date: Thursday, June 17, 2010, 11:31 AM
Good suggestion but that did not change the results.
--- On Thu, 6/17/10, Robert Jordan wrote:
From: Robert Jordan
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: mono-devel-list@lists.ximian.com
Date: Thursday, June 17, 2010, 10:53 AM
On 17.06.2010 18:07, Trevor Ackerman wrote:
> I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
> afaik) and I'm having trouble with floats when executing
code.
...
> My CFLAGS and CPPFLAGS environment variables are
> both
> -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
-DNO_UNALIGNED_ACCESS is probably needed as
well.
Robert
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
The change you posted is certainly not correct as soft float works on
all our dev boards. Could you send us the contents of /process/cpuinfo
please?
On Friday, June 18, 2010, Trevor Ackerman wrote:
> I believe it is armel, here's what 'file' reports for a natively compiled C
> program.
>
> hello_world_c: ELF 32-bit LSB executable, ARM, version 1, dynamically linked
> (uses shared libs), not stripped.
>
> Let me know if you still believe it is a bug and how I may contribute a
> solution, whether the example change I posted is appropriate or not.
>
> Thanks
>
> --- On Thu, 6/17/10, Geoff Norton wrote:
>
> From: Geoff Norton
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: "Trevor Ackerman"
> Cc: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 9:54 PM
>
> Is your system armeb or
> armel?
> It could be a endian bug in our softfloat impl somewhere.
> -g
> On 2010-06-17, at 7:54 PM, Trevor Ackerman wrote:
> I have more to report.
>
> I wrote a quick native C program to print out the bytes of a float and double
> variable that were assigned the literal value 1.0f.
>
> Then in the mono 2.6.4 routine mono_method_to_ir in source code file
> mono/mini/method_to_ir.c I dumped out the bytes of ip (instruction pointer)
> used for the double value in the case for CEE_LDC_R8.
>
> I discovered that the bytes in the double value used on mono had the high and
> low 32 bits swapped compared to those produced by the native C program. I
> hacked the routine decompose_soft_float to swap the high and low
> words and now I have no troubles and the basic-float regression test passes
> 100%.
>
> Although this happens to work, I have a hard time believing that this is the
> correct solution to my problem. I feel that others are probably using ARM9
> without
> floating point issues and that I am probably missing something in how I
> built mono for my platform. If anyone can shed some light on what I did wrong
> with building mono that'd be great. Of course if this is the correct action
> to take please let me know that too and how I may contribute the change back
> to the trunk (assuming that the trunk doesn't work which I haven't had time
> to test yet).
>
> In the meantime here's my hack to decompose_soft_float in method-to-ir.c
>
>
> 5073 case OP_R8CONST: {
> 5074 unsigned char *ucp = (unsigned char *) ins->inst_p0;
> 5075 unsigned char
> rawval[8];
> 5076 printf("decompose_soft_float OP_R8CONST\n");
> 5077 rawval[0] =
> ucp[4];
> 5078 rawval[1] = ucp[5];
> 5079 rawval[2] = ucp[6];
> 5080 rawval[3] = ucp[7];
> 5081 rawval[4] = ucp[0];
> 5082 rawval[5] = ucp[1];
> 5083 rawval[6] = ucp[2];
> 5084 rawval[7] = ucp[3];
> 5085 DVal d;
> 5086
> // d.vald = *(double*)ins->inst_p0;
> 5087 d.vald = *(double*)rawval;
> 5088 MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
> 5089 break;
> 5090 }
>
> --- On Thu, 6/17/10, Trevor Ackerman
> http://mc/compose?to=t_acker...@yahoo.com>> wrote:
>
> From: Trevor Ackerman
> http://mc/compose?to=t_acker...@yahoo.com>>
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 11:31 AM
>
> Good suggestion but that did not change the results.
>
> --- On Thu, 6/17/10, Robert Jordan
> http://mc/compose?to=robe...@gmx.net>> wrote:
>
> From: Robert Jordan http://mc/compose?to=robe...@gmx.net>>
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 10:53 AM
>
> On 17.06.2010 18:07, Trevor Ackerman wrote:
>> I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
>> afaik) and I'm having trouble with floats when executing
> code.
>
> ...
>
>> My CFLAGS and CPPFLAGS environment variables are
>> both
>> -DARM_FPU_NONE=1 -DMONO_ARCH_SOFT_FLOAT=1
>
> -DNO_UNALIGNED_ACCESS is probably needed as
> well.
>
> Robert
>
> ___
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> http://lists.ximian.com/mailman/listinfo/mono-devel-list
>
>
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>
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
~ # cat /proc/cpuinfo
Processor : ARM926EJ-S rev 5 (v5l)
BogoMIPS : 74.34
Features : swp half fastmult edsp java
CPU implementer : 0x41
CPU architecture: 5TEJ
CPU variant : 0x0
CPU part : 0x926
CPU revision : 5
Hardware : ConnectCore 9P 9215 on a JSCC9P9215 Devboard
Revision :
Serial :
--- On Fri, 6/18/10, Geoff Norton wrote:
From: Geoff Norton
Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
To: "Trevor Ackerman"
Cc: "mono-devel-list@lists.ximian.com"
Date: Friday, June 18, 2010, 9:41 AM
The change you posted is certainly not correct as soft float works on
all our dev boards. Could you send us the contents of /process/cpuinfo
please?
On Friday, June 18, 2010, Trevor Ackerman wrote:
> I believe it is armel, here's what 'file' reports for a natively compiled C
> program.
>
> hello_world_c: ELF 32-bit LSB executable, ARM, version 1, dynamically linked
> (uses shared libs), not stripped.
>
> Let me know if you still believe it is a bug and how I may contribute a
> solution, whether the example change I posted is appropriate or not.
>
> Thanks
>
> --- On Thu, 6/17/10, Geoff Norton wrote:
>
> From: Geoff Norton
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: "Trevor Ackerman"
> Cc: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 9:54 PM
>
> Is your system armeb or
> armel?
> It could be a endian bug in our softfloat impl somewhere.
> -g
> On 2010-06-17, at 7:54 PM, Trevor Ackerman wrote:
> I have more to report.
>
> I wrote a quick native C program to print out the bytes of a float and double
> variable that were assigned the literal value 1.0f.
>
> Then in the mono 2.6.4 routine mono_method_to_ir in source code file
> mono/mini/method_to_ir.c I dumped out the bytes of ip (instruction pointer)
> used for the double value in the case for CEE_LDC_R8.
>
> I discovered that the bytes in the double value used on mono had the high and
> low 32 bits swapped compared to those produced by the native C program. I
> hacked the routine decompose_soft_float to swap the high and low
> words and now I have no troubles and the basic-float regression test passes
>100%.
>
> Although this happens to work, I have a hard time believing that this is the
> correct solution to my problem. I feel that others are probably using ARM9
> without
> floating point issues and that I am probably missing something in how I
>built mono for my platform. If anyone can shed some light on what I did wrong
>with building mono that'd be great. Of course if this is the correct action to
>take please let me know that too and how I may contribute the change back to
>the trunk (assuming that the trunk doesn't work which I haven't had time to
>test yet).
>
> In the meantime here's my hack to decompose_soft_float in method-to-ir.c
>
>
> 5073 case OP_R8CONST: {
> 5074 unsigned char *ucp = (unsigned char *) ins->inst_p0;
> 5075 unsigned char
> rawval[8];
> 5076 printf("decompose_soft_float OP_R8CONST\n");
> 5077 rawval[0] =
> ucp[4];
> 5078 rawval[1] = ucp[5];
> 5079 rawval[2] = ucp[6];
> 5080 rawval[3] = ucp[7];
> 5081 rawval[4] = ucp[0];
> 5082 rawval[5] = ucp[1];
> 5083 rawval[6] = ucp[2];
> 5084 rawval[7] = ucp[3];
> 5085 DVal d;
> 5086
> // d.vald = *(double*)ins->inst_p0;
> 5087 d.vald = *(double*)rawval;
> 5088 MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
> 5089 break;
> 5090 }
>
> --- On Thu, 6/17/10, Trevor Ackerman
> http://mc/compose?to=t_acker...@yahoo.com>> wrote:
>
> From: Trevor Ackerman
> http://mc/compose?to=t_acker...@yahoo.com>>
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 11:31 AM
>
> Good suggestion but that did not change the results.
>
> --- On Thu, 6/17/10, Robert Jordan
> http://mc/compose?to=robe...@gmx.net>> wrote:
>
> From: Robert Jordan http://mc/compose?to=robe...@gmx.net>>
> Subject: Re: [Mono-dev] Arm9 NS9215 floating point troubles
> To: mono-devel-list@lists.ximian.com
> Date: Thursday, June 17, 2010, 10:53 AM
>
> On 17.06.2010 18:07, Trevor Ackerman wrote:
>> I have been able to cross-compile Mono 2.6.4 for the NS9215 (no fpu
>> afaik) and I'm having trouble with floats when executing
Re: [Mono-dev] Arm9 NS9215 floating point troubles
I'm having a similar problem. I'm using a Freescale mc9328mxs processor
(ARM920T core) that doesn't have hardware floating point. I've tried
Trevor's C# test code and the console outputs incorrect floating point
values. I have also tried Trevor's hack to method-to-ir.c and it doesn't
help for me.
Example:
Console.WriteLine("0.0f literal is " + 0.0f);
Console.WriteLine("1.0f literal is " + 1.0f);
Console.WriteLine("12.3f literal is " + 12.3f);
Console.WriteLine("32f literal is " + 32f);
Console.WriteLine("1024f literal is " + 1024f);
Console.WriteLine("32768f literal is " + 32768f);
Also when the application exits main(), I get an exception.
Unhandled Exception: System.TypeInitializationException: An exception was
thrown
by the type initializer for System.Runtime.Remoting.Contexts.Context --->
Syste
m.ArgumentOutOfRangeException: load factor
Parameter name: loadFactor
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor,
IHas
hCodeProvider hcp, IComparer comparer) [0x0]
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor)
[0x0
]
at System.Collections.Hashtable..ctor () [0x0]
at System.Runtime.Remoting.Contexts.Context..cctor () [0x0]
I've spent days trying to figure this out. Any help is appreciated.
Thanks.
--
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
There seems to be an endianness problem when the floating point value goes to
the JIT. I used Trevor's code and changed the byte order and my problems
disappeared.
In method-to-ir.c:
case OP_R8CONST: {
DVal d;
// ORIGINAL CODE
//d.vald = *(double*)ins->inst_p0;
//MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
// NEW CODE TO CHANGE ENDIANNESS
unsigned char *ucp = (unsigned char *) ins->inst_p0;
unsigned char rawval[8];
rawval[0] = ucp[7];
rawval[1] = ucp[6];
rawval[2] = ucp[5];
rawval[3] = ucp[4];
rawval[4] = ucp[3];
rawval[5] = ucp[2];
rawval[6] = ucp[1];
rawval[7] = ucp[0];
d.vald = *(double*)rawval;
MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
break;
}
case OP_R4CONST: {
DVal d;
// ORIGINAL CODE
/* We load the r8 value */
//d.vald = *(float*)ins->inst_p0;
//MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
// NEW CODE TO CHANGE ENDIANNESS
unsigned char *ucp = (unsigned char *) ins->inst_p0;
unsigned char rawval[4];
rawval[0] = ucp[3];
rawval[1] = ucp[2];
rawval[2] = ucp[1];
rawval[3] = ucp[0];
d.vald = *(double*)rawval;
MONO_EMIT_NEW_I8CONST (cfg, ins->dreg, d.vall);
break;
}
Thanks Trevor!
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Re: [Mono-dev] Arm9 NS9215 floating point troubles
I'm having a similar problem. I'm using a Freescale mc9328mxs processor that
doesn't have hardware floating point. I've tried Trevor's C# test code and
the console outputs incorrect floating point values. I have also tried
Trevor's hack to method-to-ir.c and it doesn't help for me.
Example:
Console.WriteLine("0.0f literal is " + 0.0f);
Console.WriteLine("1.0f literal is " + 1.0f);
Console.WriteLine("12.3f literal is " + 12.3f);
Console.WriteLine("32f literal is " + 32f);
Console.WriteLine("1024f literal is " + 1024f);
Console.WriteLine("32768f literal is " + 32768f);
Also when the application exits main(), I get an exception.
Unhandled Exception: System.TypeInitializationException: An exception was
thrown
by the type initializer for System.Runtime.Remoting.Contexts.Context --->
Syste
m.ArgumentOutOfRangeException: load factor
Parameter name: loadFactor
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor,
IHas
hCodeProvider hcp, IComparer comparer) [0x0]
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor)
[0x0
]
at System.Collections.Hashtable..ctor () [0x0]
at System.Runtime.Remoting.Contexts.Context..cctor () [0x0]
I've spent days trying to figure this out. Any help is appreciated.
Thanks.
--
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http://mono.1490590.n4.nabble.com/Arm9-NS9215-floating-point-troubles-tp2259090p2324899.html
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