[pypy-dev] PPC JIT test_load_and_store()

[Sven Hager]

On 08/18/2011 04:50 PM, David Edelsohn wrote:
> To be more concrete, the current test code is
>
>      def test_load_and_store(self):
>          a = PPCBuilder()
>          word1 = 1000
>          word2 = 2000
>          a.load_word(10, word1)   # load constant 1000 into r10
>          a.load_word(11, word2)   # load constant 2000 into r11
>          a.stw(10, 8, 0)                # store r10 into memory at address in r8
>          a.stw(11, 9, 0)                # store r11 into memory at address in r9
>          a.lwz(4, 8, 0)                  # load r4 from memory at address in r8
>          a.lwz(5, 9, 0)                  # load r5 from memory at address in r9
>          a.add(3, 4, 5)                 # r3 = r4 + r5
>          a.blr()
>          f = a.assemble()
>          assert f() == word1 + word2
>
> r8 and r9 are not initialized and point to whatever locations those
> registers happen to hold. In libffi for PPC, r8 happens to hold the
> arg pointer, but there are no arguments and r9 is arbitrary.
>
> In both PPC32 and PPC64 libffi, r7 points to the function address, so
> a version that overwrites the beginning of the code produced by the
> JIT and already executed is
>
>          a.stw(10, 7, 0)
>          a.stw(11, 7, 4)
>          a.lwz(4, 7, 0)
>          a.lwz(5, 7, 4)
>
> Thanks, David
Hi David,

thank you for telling me about the broken test.
I fixed the problem, as Armin recommended, and also added your
pathh no. 5 to the code.

Tomorrow I will fix the broken import paths.

Best regards,
Sven