[AMDGPU] AsmPrinter: Unify arg handling (#151672)

When computing the number of registers required by entry functions, the
`AMDGPUAsmPrinter` needs to take into account both the register usage
computed by the `AMDGPUResourceUsageAnalysis` pass, and the number
of registers initialized by the hardware. At the moment, the way it
computes the latter is different for graphics vs compute, due to differences in
the implementation. For kernels, all the information needed is available in
the `SIMachineFunctionInfo`, but for graphics shaders we would iterate over
the `Function`  arguments in the `AMDGPUAsmPrinter`. This pretty much 
repeats some of the logic from instruction selection.

This patch introduces 2 new members to `SIMachineFunctionInfo`, one
for SGPRs and one for VGPRs. Both will be computed during instruction
selection and then used during `AMDGPUAsmPrinter`, removing the need
to refer to the `Function` when printing assembly.

This patch is NFC except for the fact that we now add the extra SGPRs
(VCC, XNACK etc) to the number of SGPRs computed for graphics entry points.
I'm not sure why these weren't included before. It would be nice if
someone could confirm if that was just an oversight or if we have some docs
somewhere that I haven't managed to find. Only one test is affected (its SGPR
usage increases because we now take into account the XNACK registers).

0 files changed, 0 insertions, 0 deletions