[llvm-commits] [PATCH 08/11] (patch) Mips specific inline asm: constraint 'O':

[Eric Christopher]

On Apr 12, 2012, at 1:51 PM, Jack Carter <jcarter at mips.com> wrote:

> A signed 15 bit constant.
> 
> Example:
> 
>  short s_input = 7;short s_result = 0;
> 
>  // Good: value is within range.
>  short s_val = 16383;
>  __asm__ __volatile__(
>    "addi %0,%1,%2" : "=r" (s_result)  : "r" (s_input), "O" (s_val));
>  printf ("mips_addi(%d,%d) = %d\n", s_input, s_val, s_result);
> 
>  // Good: value is still within range.
>  short s_val = -16383;
>  __asm__ __volatile__(
>    "addi %0,%1,%2" : "=r" (s_result)  : "r" (s_input), "O" (s_val));
>  printf ("mips_addi(%d,%d) = %d\n", s_input, s_val, s_result);
> 
>  // Bad: value is out of range. llc should produce an error
>  short s_val = 16384;
>  __asm__ __volatile__(
>    "addi %0,%1,%2" : "=r" (s_result)  : "r" (s_input), "O" (s_val));
>  printf ("mips_addi(%d,%d) = %d\n", s_input, s_val, s_result);
> ---
> lib/Target/Mips/MipsISelLowering.cpp         |   11 +++++++++++
> test/CodeGen/Mips/inlineasm-cnstrnt-bad-O.ll |   13 +++++++++++++
> test/CodeGen/Mips/inlineasm_constraint.ll    |    6 ++++++
> 3 files changed, 30 insertions(+), 0 deletions(-)

Slight problem here. I don't like using XFAIL for "this should fail" type of tests. You'll need to come up with another way to test this one.

-eric