llvm-project

230c13d5 - [AMDGPU] Pick available high VGPR for CSR SGPR spilling (#78669)

[AMDGPU] Pick available high VGPR for CSR SGPR spilling (#78669) CSR SGPR spilling currently uses the early available physical VGPRs. It currently imposes a high register pressure while trying to allocate large VGPR tuples within the default register budget. This patch changes the spilling strategy by picking the VGPRs in the reverse order, the highest available VGPR first and later after regalloc shift them back to the lowest available range. With that, the initial VGPRs would be available for allocation and possibility of finding large number of contiguous registers will be more.