Compiler/C2000-CGT: About TI v6.2.8 compiler OR Operation [Optimization level : 3 interprocedure optimization]

user6451810

Part Number: C2000-CGT

Tool/software: TI C/C++ Compiler

TI v6.2.8 compiler, when the [3 interprocedure optimization] is selected, the first OR operation (tmp_1st |= 0xFFFFFF00) of the following code will be optimized as follows,

The high eight bits of the variable tmp_1st are not assigned, which results in an error in the result of the operation. The second OR operation has no problem.

I tried to use a higher version of the compiler (TI v18.1.4.LTS) and confirmed the phenomenon.

The above problems will not occur when the same code is executed and the [3 interprocedure optimization] are executed.

Is it a problem with the compiler TI v6.2.8?

.c file

.asm file

TI v6.2.8

Optimization level：3 Interprocedure Optimizations

over 5 years ago

0 user6451810 over 5 years ago

Prodigy 50 points

4540.test.c

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#include <stdio.h>
unsigned pData[2] = {1,2};
typedef union{
    unsigned Word[2];
    unsigned long Dword;
}wordDWord;
long value_1st,value_2nd = 0;
int main(void) {
    
    long tmp_1st,tmp_2nd;
    if(0x0080 & tmp_1st){
        tmp_1st |= 0xFFFFFF00;
    }
    if(0x0080 & tmp_2nd){
        tmp_2nd = tmp_2nd | 0xFFFFFF00;
    }
    value_1st = tmp_1st;
    value_2nd = tmp_2nd;
    return 0;
}
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#include <stdio.h>

unsigned pData[2] = {1,2};

typedef union{
	unsigned Word[2];
	unsigned long Dword;
}wordDWord;

long value_1st,value_2nd = 0;

int main(void) {
	
	long tmp_1st,tmp_2nd;

	if(0x0080 & tmp_1st){
		tmp_1st |= 0xFFFFFF00;
	}

	if(0x0080 & tmp_2nd){
		tmp_2nd = tmp_2nd | 0xFFFFFF00;
	}

	value_1st = tmp_1st;
	value_2nd = tmp_2nd;

	return 0;
}

test.asm

0 George Mock over 5 years ago

TI__Guru**** 244300 points

For the source file which has this problem, please follow the directions in the article How to Submit a Compiler Test Case.

Version 6.2.8 is about 6 years old, and it is no longer supported. But I might be able to find a workaround. And I would like to make sure the problem is not present in current versions of the compiler.

Thanks and regards,

-George

0 user6451810 over 4 years ago in reply to George Mock

Prodigy 50 points

Sorry for the late reply, please delete my question, thank you

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Compiler/C2000-CGT: About TI v6.2.8 compiler OR Operation [Optimization level : 3 interprocedure optimization]