[v3,3/3] RISC-V: Limit regs use for z[f/d]inx extension.
Commit Message
From: Jia-Wei Chen <jiawei@iscas.ac.cn>
Limit zfinx abi support with 'ilp32','ilp32e','lp64' only.
Use GPR instead FPR when 'zfinx' enable, Only use even registers in RV32 when 'zdinx' enable.
gcc/ChangeLog:
* config/riscv/constraints.md (TARGET_HARD_FLOAT ? FP_REGS :
((TARGET_ZFINX || TARGET_ZDINX) ? GR_REGS : NO_REGS)):
Use gpr when zfinx or zdinx enable.
* config/riscv/riscv.c (riscv_hard_regno_mode_ok): Add TARGET_ZFINX.
(riscv_option_override): Ditto.
(riscv_abi): Add ABI limit for zfinx with ilp32/lp64.
Co-Authored-By: Sinan Lin.
---
gcc/config/riscv/constraints.md | 4 ++--
gcc/config/riscv/riscv.cc | 14 +++++++++++++-
2 files changed, 15 insertions(+), 3 deletions(-)
@@ -21,8 +21,8 @@
;; Register constraints
-(define_register_constraint "f" "TARGET_HARD_FLOAT ? FP_REGS : NO_REGS"
- "A floating-point register (if available).")
+(define_register_constraint "f" "TARGET_HARD_FLOAT ? FP_REGS : ((TARGET_ZFINX || TARGET_ZDINX) ? GR_REGS : NO_REGS)"
+ "A floating-point register (if available, reuse GPR as FPR when use zfinx).")
(define_register_constraint "j" "SIBCALL_REGS"
"@internal")
@@ -4789,6 +4789,13 @@ riscv_hard_regno_mode_ok (unsigned int regno, machine_mode mode)
!= call_used_or_fixed_reg_p (regno + i))
return false;
+ /* Only use even registers in RV32 ZDINX */
+ if (!TARGET_64BIT && TARGET_ZDINX){
+ if (GET_MODE_CLASS (mode) == MODE_FLOAT &&
+ GET_MODE_UNIT_SIZE (mode) == GET_MODE_SIZE (DFmode))
+ return !(regno & 1);
+ }
+
return true;
}
@@ -4980,7 +4987,7 @@ riscv_option_override (void)
error ("%<-mdiv%> requires %<-march%> to subsume the %<M%> extension");
/* Likewise floating-point division and square root. */
- if (TARGET_HARD_FLOAT && (target_flags_explicit & MASK_FDIV) == 0)
+ if ((TARGET_HARD_FLOAT || TARGET_ZFINX) && (target_flags_explicit & MASK_FDIV) == 0)
target_flags |= MASK_FDIV;
/* Handle -mtune, use -mcpu if -mtune is not given, and use default -mtune
@@ -5026,6 +5033,11 @@ riscv_option_override (void)
if (TARGET_RVE && riscv_abi != ABI_ILP32E)
error ("rv32e requires ilp32e ABI");
+ // Zfinx require abi ilp32,ilp32e or lp64.
+ if (TARGET_ZFINX && riscv_abi != ABI_ILP32
+ && riscv_abi != ABI_LP64 && riscv_abi != ABI_ILP32E)
+ error ("z*inx requires ABI ilp32, ilp32e or lp64");
+
/* We do not yet support ILP32 on RV64. */
if (BITS_PER_WORD != POINTER_SIZE)
error ("ABI requires %<-march=rv%d%>", POINTER_SIZE);