Bit Access Bug...

[Mac 0]

Found following bit access problem using BoostC version 6.87;

 

//  BoostC code

unsigned int TxChar = 0;

void main()
{
 TxChar.4 = 1;	 // set bit 4
 TxChar.9 = 1;	 // set bit 9
}

//  assembler output sets bit 1 in the low byte rather than
//  bit 1 in the high byte at "gbl_TxChar+d'1'"
//
//	0052  1623	  BSF gbl_TxChar,4
//	0053  14A4	  BSF gbl_TxChar,1

[Reynard 0]

Definitely a bug.

 

Workaround:

 

set_bit(TxChar,9); or TxChar |= (1 << 9); seem to work.

 

Cheers

 

Reynard

[cac001 0]

Definitely not a bug:

;Address  Opcode  Disassembly
; 052	 1623	BSF 0x23, 0x4						  
; 053	 14A4	BSF 0x24, 0x1

[Pavel 0]

Found following bit access problem using BoostC version 6.87;

 

//  BoostC code

unsigned int TxChar = 0;

void main()
{
 TxChar.4 = 1;	 // set bit 4
 TxChar.9 = 1;	 // set bit 9
}

//  assembler output sets bit 1 in the low byte rather than
//  bit 1 in the high byte at "gbl_TxChar+d'1'"
//
//	0052  1623	  BSF gbl_TxChar,4
//	0053  14A4	  BSF gbl_TxChar,1

 

For this code correct opcodes get generated. Your program will run as intended. It's only the instruction that gets displayed incorrectly as if it uses low byte. So the reported problem seems not to be a problem but it reveals another one that is a problem though much more minor.

 

Regards,

Pavel

[Mac 0]

For this code correct opcodes get generated. Your program will run as intended. It's only the instruction that gets displayed incorrectly as if it uses low byte. So the reported problem seems not to be a problem but it reveals another one that is a problem though much more minor.

 

Regards,

Pavel

Thank you Pavel...

 

Mike