Some of these tests did not specify a cpu but were also sensitive to
instruction scheduling and/or register assignment choices. A few others
similarly-sensitive tests specified a cpu (often the POWER7), and while the P7
currently uses the default model for PPC64, this will soon change. For those
tests which should not really be cpu-dependent anyway, the cpu is set to the
generic 'ppc64'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195977 91177308-0d34-0410-b5e6-96231b3b80d8
to be extended to a full register. This is modeled in the IR by marking
the return value (or argument) with a signext or zeroext attribute.
However, while these attributes are respected for function arguments,
they are currently ignored for function return values by the PowerPC
back-end. This patch updates PPCCallingConv.td to ask for the promotion
to i64, and fixes LowerReturn and LowerCallResult to implement it.
The new test case verifies that both arguments and return values are
properly extended when passing them; and also that the optimizers
understand incoming argument and return values are in fact guaranteed
by the ABI to be extended.
The patch caused a spurious breakage in CodeGen/PowerPC/coalesce-ext.ll,
since the test case used a "ret" instruction to create a use of an i32
value at the end of the function (to set up data flow as required for
what the test is intended to test). Since there's now an implicit
promotion to i64, that data flow no longer works as expected. To fix
this, this patch now adds an extra "add" to ensure we have an appropriate
use of the i32 value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167396 91177308-0d34-0410-b5e6-96231b3b80d8
The PPC::EXTSW instruction preserves the low 32 bits of its input, just
like some of the x86 instructions. Use it to reduce register pressure
when the low 32 bits have multiple uses.
This requires a small change to PeepholeOptimizer since EXTSW takes a
64-bit input register.
This is related to PR5997.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158743 91177308-0d34-0410-b5e6-96231b3b80d8
