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Re: RESUBMIT: PowerPC -- support single-precision FPU
- From: "David Edelsohn" <dje dot gcc at gmail dot com>
- To: "Michael Eager" <eager at eagercon dot com>
- Cc: "Andreas Tobler" <andreast-list at fgznet dot ch>, janis187 at us dot ibm dot com, "GCC Patches" <gcc-patches at gcc dot gnu dot org>, "Andrew Pinski" <pinskia at gmail dot com>
- Date: Thu, 2 Oct 2008 15:28:16 -0400
- Subject: Re: RESUBMIT: PowerPC -- support single-precision FPU
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On Thu, Oct 2, 2008 at 3:23 PM, Michael Eager <firstname.lastname@example.org> wrote:
> I'm not sure that removing the test for TARGET_SINGLE_FLOAT
> in USE_FP_FOR_ARG_P is correct. On a target with a single-precision
> FPU, only SFmode values can be passed in FP regs. This change says
> that DFmode values are can be passed in FP regs, even if
> TARGET_DOUBLE_FLOAT is false.
> Removing the test in rs6000_function_value() means that
> FP_ARG_RETURN will be used to return all FP values. That's
> not correct on a single-precision FPU for DFmode values.
> I'll admit to being confused about TFmode. This seems to
> sneak in with DFmode.
I did not mean to imply that my patch was the final, correct implementation
for the Xilinx functionality. I meant this returns GCC to correct behavior
for existing architectures and ABIs.