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bpf: neg instruction does not accept an immediate

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The BPF virtual machine does not support neg nor neg32 instructions with
an immediate.

The erroneous instructions were removed from binutils:
https://sourceware.org/pipermail/binutils/2023-August/129135.html

Change the define_insn so that an immediate cannot be accepted.

From testing, a neg-immediate was probably never chosen over a
mov-immediate anyway.

gcc/

	* config/bpf/bpf.md (neg): Second operand must be a register.
This commit is contained in:
David Faust 2023-08-21 13:34:08 -07:00
parent 36788c9ff6
commit e2c42860b6
1 changed files with 2 additions and 2 deletions
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4
gcc/config/bpf/bpf.md
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@ -163,8 +163,8 @@
;;; Negation
(define_insn "neg<AM:mode>2"
[(set (match_operand:AM 0 "register_operand" "=r,r")
(neg:AM (match_operand:AM 1 "reg_or_imm_operand" " 0,I")))]
[(set (match_operand:AM 0 "register_operand" "=r")
(neg:AM (match_operand:AM 1 "register_operand" " 0")))]
""
"{neg<msuffix>\t%0|%w0 = -%w1}"
[(set_attr "type" "<mtype>")])