32-bit floating point divide mishandles inputs that should return negative infinity, and division by zero

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    • Type: Bug
    • Resolution: Unresolved
    • Priority: Low

      The attached C file has this small program ...

      #include <stdio.h>

int main(void)
{
    float f1, f2;

    f1 =  1.75e+34f;
    f2 = -1.96e-07f;
    printf("expect negative infinity, get %g\n", f1/f2);

    f1 = 1.0f;
    f2 = 0.0f;
    printf("expect 0x7f7fffff, get 0x%lx\n",  __f32_bits_as_u32(f1/f2));

    f1 = -1.0f;
    f2 = 0.0f;
    printf("expect 0xff7fffff, get 0x%lx\n",  __f32_bits_as_u32(f1/f2));

	return 0;
}

      Build with no optimization, so the RTS function for 32-bit floating point divide is called.
      When it runs, this is the output ...

      expect negative infinity, get 2.35099e-38
expect 0x7f7fffff, get 0x7f7f0000
expect 0xff7fffff, get 0xff7f0000

            Assignee:
            TI User
            Reporter:
            TI User
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            1 Vote for this issue
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              Created:
              Updated:

                Connection: Intermediate to External PROD System
                EXTSYNC-3660 - 32-bit floating point divide mishan...
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