Implement neg using OP_ADD

We have all the machinery in place to implement the neg instruction
as OP_ADD.  Doing that means we can ditch OP_NEG, and saves about
66 slice LUTs on the A7-100.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
pull/104/head
Paul Mackerras 4 years ago
parent 6c4edf80ae
commit 86c53aa3f7

@ -243,7 +243,7 @@ architecture behaviour of decode1 is
2#0011101001# => (MUL, OP_MUL_L64, RA, RB, NONE, RT, '0', '1', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '1', RC, '0', '1'), -- mulld
2#0011101011# => (MUL, OP_MUL_L64, RA, RB, NONE, RT, '0', '1', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '1', RC, '0', '1'), -- mullw
2#0111011100# => (ALU, OP_AND, NONE, RB, RS, RA, '0', '0', '0', '1', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- nand
2#0001101000# => (ALU, OP_NEG, RA, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- neg
2#0001101000# => (ALU, OP_ADD, RA, NONE, NONE, RT, '0', '0', '1', '0', ONE, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- neg
2#0001111100# => (ALU, OP_OR, NONE, RB, RS, RA, '0', '0', '0', '1', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- nor
2#0110111100# => (ALU, OP_OR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- or
2#0110011100# => (ALU, OP_OR, NONE, RB, RS, RA, '0', '0', '1', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- orc

@ -13,7 +13,7 @@ package decode_types is
OP_LOAD, OP_STORE, OP_MADDHD, OP_MADDHDU, OP_MADDLD, OP_MCRF,
OP_MCRXR, OP_MCRXRX, OP_MFCR, OP_MFSPR, OP_MOD,
OP_MTCRF, OP_MTSPR, OP_MUL_L64,
OP_MUL_H64, OP_MUL_H32, OP_NEG, OP_OR,
OP_MUL_H64, OP_MUL_H32, OP_OR,
OP_POPCNTB, OP_POPCNTD, OP_POPCNTW, OP_PRTYD,
OP_PRTYW, OP_RLC, OP_RLCL, OP_RLCR, OP_SETB,
OP_SHL, OP_SHR,

@ -311,9 +311,6 @@ begin
elsif std_match(e_in.insn(20 downto 11), "0100000000") then
ctrl_tmp.lr <= e_in.read_data3;
end if;
when OP_NEG =>
result := ppc_neg(e_in.read_data1);
result_en := 1;
when OP_POPCNTB =>
result := ppc_popcntb(e_in.read_data3);
result_en := 1;

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