When compiling glibc we found that the GOT register was being allocated
r9 when the instruction was still set_got_tmp. That caused set_got to
clobber r9. We cannot simply say set_got_tmp clobbers r9 as this is the
reason for having the temporary set_got_tmp.
Fix by using a register class constraint that does not allow r9 during
register allocation.
gcc/ChangeLog:
* config/or1k/constraints.md (t): New constraint.
* config/or1k/or1k.h (GOT_REGS): New register class.
* config/or1k/or1k.md (set_got_tmp, set_got): Use t contraint.
---
gcc/config/or1k/constraints.md | 4 ++++
gcc/config/or1k/or1k.h | 3 +++
gcc/config/or1k/or1k.md | 4 ++--
3 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/gcc/config/or1k/constraints.md b/gcc/config/or1k/constraints.md
index 8cac7eb5329..ba330c6b8c2 100644
--- a/gcc/config/or1k/constraints.md
+++ b/gcc/config/or1k/constraints.md
@@ -25,6 +25,7 @@
; We use:
; c - sibcall registers
; d - double pair base registers (excludes r0, r30 and r31 which overflow)
+; t - got address registers (excludes r9 is clobbered by set_got)
; I - constant signed 16-bit
; K - constant unsigned 16-bit
; M - constant signed 16-bit shifted left 16-bits (l.movhi)
@@ -36,6 +37,9 @@
(define_register_constraint "d" "DOUBLE_REGS"
"Registers which can be used for double reg pairs.")
+(define_register_constraint "t" "GOT_REGS"
+ "Registers which can be used to store the Global Offset Table (GOT)
address.")
+
;; Immediates
(define_constraint "I"
"A signed 16-bit immediate in the range -32768 to 32767."
diff --git a/gcc/config/or1k/or1k.h b/gcc/config/or1k/or1k.h
index 2b29e62fdd3..4c32607bac1 100644
--- a/gcc/config/or1k/or1k.h
+++ b/gcc/config/or1k/or1k.h
@@ -190,6 +190,7 @@ enum reg_class
NO_REGS,
SIBCALL_REGS,
DOUBLE_REGS,
+ GOT_REGS,
GENERAL_REGS,
FLAG_REGS,
ALL_REGS,
@@ -202,6 +203,7 @@ enum reg_class
"NO_REGS", \
"SIBCALL_REGS", \
"DOUBLE_REGS", \
+ "GOT_REGS", \
"GENERAL_REGS", \
"FLAG_REGS", \
"ALL_REGS" }
@@ -215,6 +217,7 @@ enum reg_class
{ { 0x00000000, 0x00000000 }, \
{ SIBCALL_REGS_MASK, 0 }, \
{ 0x7f7ffffe, 0x00000000 }, \
+ { 0xfffffdff, 0x00000000 }, \
{ 0xffffffff, 0x00000003 }, \
{ 0x00000000, 0x00000004 }, \
{ 0xffffffff, 0x00000007 } \
diff --git a/gcc/config/or1k/or1k.md b/gcc/config/or1k/or1k.md
index cee11d078cc..36bcee336ab 100644
--- a/gcc/config/or1k/or1k.md
+++ b/gcc/config/or1k/or1k.md
@@ -706,7 +706,7 @@
;; set_got pattern below. This works because the set_got_tmp insn is the
;; first insn in the stream and that it isn't moved during RA.
(define_insn "set_got_tmp"
- [(set (match_operand:SI 0 "register_operand" "=r")
+ [(set (match_operand:SI 0 "register_operand" "=t")
(unspec_volatile:SI [(const_int 0)] UNSPECV_SET_GOT))]
""
{
@@ -715,7 +715,7 @@
;; The insn to initialize the GOT.
(define_insn "set_got"
- [(set (match_operand:SI 0 "register_operand" "=r")
+ [(set (match_operand:SI 0 "register_operand" "=t")
(unspec:SI [(const_int 0)] UNSPEC_SET_GOT))
(clobber (reg:SI LR_REGNUM))]
""
--
2.21.0
