Re: [committed] amdgcn: add -march=gfx1030 EXPERIMENTAL

[Andrew Stubbs]

On 20/10/2023 12:51, Andrew Stubbs wrote:
I've committed this patch that allows building binaries for AMD gfx1030 
GPUs. I can't actually test it, however, so somebody else will have to 
debug it (or wait for me to get my hands on a device). Richi reports 
that it does not execute correctly, as is.

The patch introduced a bug returning exit values that affected all the 
targets. I've now committed a patch to fix the issue.

Andrewamdgcn: Fix bug in gfx1030 support patch

The previous patch to add gfx1030 support introduced an issue with passing
exit codes from kernels run under gcn-run (offload kernels were unaffected).

gcc/ChangeLog:

        PR target/112088
        * config/gcn/gcn.cc (gcn_expand_epilogue): Fix kernel epilogue register
        conflict.

diff --git a/gcc/config/gcn/gcn.cc b/gcc/config/gcn/gcn.cc
index 6f85f55803c..6a2aaefceca 100644
--- a/gcc/config/gcn/gcn.cc
+++ b/gcc/config/gcn/gcn.cc
@@ -3615,13 +3615,11 @@ gcn_expand_epilogue (void)
       set_mem_addr_space (retptr_mem, ADDR_SPACE_SCALAR_FLAT);
       emit_move_insn (kernarg_reg, retptr_mem);
 
-      rtx retval_addr = gen_rtx_REG (DImode, FIRST_VPARM_REG);
+      rtx retval_addr = gen_rtx_REG (DImode, FIRST_VPARM_REG + 2);
       emit_move_insn (retval_addr, kernarg_reg);
       rtx retval_mem = gen_rtx_MEM (SImode, retval_addr);
-      rtx scalar_retval = gen_rtx_REG (SImode, FIRST_VPARM_REG + 2);
       set_mem_addr_space (retval_mem, ADDR_SPACE_FLAT);
-      emit_move_insn (scalar_retval, gen_rtx_REG (SImode, RETURN_VALUE_REG));
-      emit_move_insn (retval_mem, scalar_retval);
+      emit_move_insn (retval_mem, gen_rtx_REG (SImode, RETURN_VALUE_REG));
     }
 
   emit_jump_insn (gen_gcn_return ());