[AMDGPU][llvm-mc] Predefined symbols to access register counts (.kernel.{v|s}gpr_count)
The feature allows for conditional assembly, filling the entries
of .amd_kernel_code_t etc.
Symbols are defined with value 0 at the beginning of each kernel scope.
After each register usage, the respective symbol is set to:
value = max( value, ( register index + 1 ) )
Thus, at the end of scope the value represents a count of used registers.
Kernel scopes begin at .amdgpu_hsa_kernel directive, end at the
next .amdgpu_hsa_kernel (or EOF, whichever comes first). There is also
dummy scope that lies from the beginning of source file til the
first .amdgpu_hsa_kernel.
Test added.
Differential Revision: https://reviews.llvm.org/D27859
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290608 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed