[gcc r11-6627] amdgcn: Remove dead code for fixed v0 register

[gcc r11-6627] amdgcn: Remove dead code for fixed v0 register

[Julian Brown]

https://gcc.gnu.org/g:7993fe1877a689463d8c71a0873e5cc8db080273

commit r11-6627-g7993fe1877a689463d8c71a0873e5cc8db080273
Author: Julian Brown <julian@codesourcery.com>
Date:   Tue Nov 24 16:42:55 2020 -0800

    amdgcn: Remove dead code for fixed v0 register
    
    This patch removes code to fix the v0 register in
    gcn_conditional_register_usage that was missed out of the previous patch
    removing the need for that:
    
      https://gcc.gnu.org/pipermail/gcc-patches/2019-November/534284.html
    
    2021-01-13  Julian Brown  <julian@codesourcery.com>
    
    gcc/
            * config/gcn/gcn.c (gcn_conditional_register_usage): Remove dead code
            to fix v0 register.

Diff:
---
 gcc/config/gcn/gcn.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/gcc/config/gcn/gcn.c b/gcc/config/gcn/gcn.c
index 630ce4eebc7..b08f4b32c9c 100644
--- a/gcc/config/gcn/gcn.c
+++ b/gcc/config/gcn/gcn.c
@@ -2137,10 +2137,6 @@ gcn_conditional_register_usage (void)
     fixed_regs[cfun->machine->args.reg[WORK_ITEM_ID_Y_ARG]] = 1;
   if (cfun->machine->args.reg[WORK_ITEM_ID_Z_ARG] >= 0)
     fixed_regs[cfun->machine->args.reg[WORK_ITEM_ID_Z_ARG]] = 1;
-
-  if (TARGET_GCN5_PLUS)
-    /* v0 is always zero, for global nul-offsets.  */
-    fixed_regs[VGPR_REGNO (0)] = 1;
 }
 
 /* Determine if a load or store is valid, according to the register classes