mono/docs/stack-alignment

Size and alignment requirements of stack values
===============================================

P  ... System.IntPtr
I1 ... System.Int8
I2 ... System.Int16
I4 ... System.Int32
I8 ... System.Int64
F  ... System.Single
D  ... System.Double
LD ... native long double

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ARCH      |   P |  I1 |  I2 |  I4 |  I8 |  F  |   D |  LD | 
-----------------------------------------------------------
X86       | 4/4 | 4/4 | 4/4 | 4/4 | 8/4 | 4/4 | 8/4 |12/4 |
-----------------------------------------------------------
X86/W32   | 4/4 | 4/4 | 4/4 | 4/4 | 8/4 | 4/4 | 8/4 |12/4 |
-----------------------------------------------------------
ARM       | 4/4 | 4/4 | 4/4 | 4/4 | 8/4 | 4/4 | 8/4 | 8/4 |
-----------------------------------------------------------
M68K      | 4/4 | 4/4 | 4/4 | 4/4 | 8/4 | 4/4 | 8/4 |12/4 |
-----------------------------------------------------------
ALPHA     | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 |
-----------------------------------------------------------
SPARC     | 4/4 | 4/4 | 4/4 | 4/4 | 8/8 | 4/4 | 8/8 |16/8 |
-----------------------------------------------------------
SPARC64   | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 | 8/8 |16/16|
-----------------------------------------------------------
MIPS      | 4/4 | 4/4 | 4/4 | 4/4 | ?/? | 4/4 | 8/8 | 8/8 |
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          |     |     |     |     |     |     |     |     |
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