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loadstore1: Add support for cache-inhibited load and store instructions

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This adds support for lbzcix, lhzcix, lwzcix, ldcix, stbcix, sthcix,
stwcix and stdcix.  The temporary hack where accesses to addresses of
the form 0xc??????? are made non-cacheable is left in for now to avoid
making existing programs non-functional.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Paul Mackerras
2020-03-30 12:39:08 +11:00
parent 4e38c2cc21
commit 81369187c0
4 changed files with 16 additions and 3 deletions
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3
common.vhdl
View File

@@ -202,6 +202,7 @@ package common is
data : std_ulogic_vector(63 downto 0); -- data to write, unused for read data : std_ulogic_vector(63 downto 0); -- data to write, unused for read
write_reg : gpr_index_t; write_reg : gpr_index_t;
length : std_ulogic_vector(3 downto 0); length : std_ulogic_vector(3 downto 0);
ci : std_ulogic; -- cache-inhibited load/store
byte_reverse : std_ulogic; byte_reverse : std_ulogic;
sign_extend : std_ulogic; -- do we need to sign extend? sign_extend : std_ulogic; -- do we need to sign extend?
update : std_ulogic; -- is this an update instruction? update : std_ulogic; -- is this an update instruction?
@@ -210,7 +211,7 @@ package common is
reserve : std_ulogic; -- set for larx/stcx. reserve : std_ulogic; -- set for larx/stcx.
rc : std_ulogic; -- set for stcx. rc : std_ulogic; -- set for stcx.
end record; end record;
constant Execute1ToLoadstore1Init : Execute1ToLoadstore1Type := (valid => '0', load => '0', byte_reverse => '0', constant Execute1ToLoadstore1Init : Execute1ToLoadstore1Type := (valid => '0', load => '0', ci => '0', byte_reverse => '0',
sign_extend => '0', update => '0', xerc => xerc_init, sign_extend => '0', update => '0', xerc => xerc_init,
reserve => '0', rc => '0', others => (others => '0')); reserve => '0', rc => '0', others => (others => '0'));

8
decode1.vhdl
View File

@@ -216,22 +216,26 @@ architecture behaviour of decode1 is
2#1111001111# => (ALU, OP_ISEL, RA_OR_ZERO, RB, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- isel 2#1111001111# => (ALU, OP_ISEL, RA_OR_ZERO, RB, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- isel
2#1111101111# => (ALU, OP_ISEL, RA_OR_ZERO, RB, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- isel 2#1111101111# => (ALU, OP_ISEL, RA_OR_ZERO, RB, NONE, RT, '1', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- isel
2#0000110100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lbarx 2#0000110100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lbarx
2#1101010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lbzcix
2#0001110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lbzux 2#0001110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lbzux
2#0001010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lbzx 2#0001010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lbzx
2#0001010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- ldarx 2#0001010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- ldarx
2#1000010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- ldbrx 2#1000010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- ldbrx
2#1101110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- ldcix
2#0000110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- ldux 2#0000110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- ldux
2#0000010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- ldx 2#0000010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- ldx
2#0001110100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lharx 2#0001110100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lharx
2#0101110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '1', '1', '0', '0', '0', NONE, '0', '0'), -- lhaux 2#0101110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '1', '1', '0', '0', '0', NONE, '0', '0'), -- lhaux
2#0101010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '1', '0', '0', '0', '0', NONE, '0', '0'), -- lhax 2#0101010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '1', '0', '0', '0', '0', NONE, '0', '0'), -- lhax
2#1100010110# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lhbrx 2#1100010110# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lhbrx
2#1100110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lhzcix
2#0100110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lhzux 2#0100110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lhzux
2#0100010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lhzx 2#0100010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lhzx
2#0000010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lwarx 2#0000010100# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '1', '0', '0', NONE, '0', '0'), -- lwarx
2#0101110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '1', '1', '0', '0', '0', NONE, '0', '0'), -- lwaux 2#0101110101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '1', '1', '0', '0', '0', NONE, '0', '0'), -- lwaux
2#0101010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '1', '0', '0', '0', '0', NONE, '0', '0'), -- lwax 2#0101010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '1', '0', '0', '0', '0', NONE, '0', '0'), -- lwax
2#1000010110# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lwbrx 2#1000010110# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lwbrx
2#1100010101# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lwzcix
2#0000110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lwzux 2#0000110111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- lwzux
2#0000010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lwzx 2#0000010111# => (LDST, OP_LOAD, RA_OR_ZERO, RB, NONE, RT, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- lwzx
-- 2#1000000000# mcrxr -- 2#1000000000# mcrxr
@@ -278,18 +282,22 @@ architecture behaviour of decode1 is
2#1100111000# => (ALU, OP_SHR, NONE, CONST_SH32, RS, RA, '0', '0', '0', '0', ZERO, '1', NONE, '0', '0', '0', '0', '1', '1', RC, '0', '0'), -- srawi 2#1100111000# => (ALU, OP_SHR, NONE, CONST_SH32, RS, RA, '0', '0', '0', '0', ZERO, '1', NONE, '0', '0', '0', '0', '1', '1', RC, '0', '0'), -- srawi
2#1000011011# => (ALU, OP_SHR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- srd 2#1000011011# => (ALU, OP_SHR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '0', '0', RC, '0', '0'), -- srd
2#1000011000# => (ALU, OP_SHR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '0', RC, '0', '0'), -- srw 2#1000011000# => (ALU, OP_SHR, NONE, RB, RS, RA, '0', '0', '0', '0', ZERO, '0', NONE, '0', '0', '0', '0', '1', '0', RC, '0', '0'), -- srw
2#1111010101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stbcix
2#1010110110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stbcx 2#1010110110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stbcx
2#0011110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stbux 2#0011110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stbux
2#0011010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stbx 2#0011010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is1B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stbx
2#1010010100# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stdbrx 2#1010010100# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stdbrx
2#1111110101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stdcix
2#0011010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stdcx 2#0011010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stdcx
2#0010110101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stdux 2#0010110101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stdux
2#0010010101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stdx 2#0010010101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is8B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stdx
2#1110010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- sthbrx 2#1110010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- sthbrx
2#1110110101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- sthcix
2#1011010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- sthcx 2#1011010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- sthcx
2#0110110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- sthux 2#0110110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- sthux
2#0110010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- sthx 2#0110010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is2B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- sthx
2#1010010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stwbrx 2#1010010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '1', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stwbrx
2#1110010101# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stwcix
2#0010010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stwcx 2#0010010110# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '1', '0', '0', ONE, '0', '0'), -- stwcx
2#0010110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stwux 2#0010110111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '1', '0', '0', '0', NONE, '0', '0'), -- stwux
2#0010010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stwx 2#0010010111# => (LDST, OP_STORE, RA_OR_ZERO, RB, RS, NONE, '0', '0', '0', '0', ZERO, '0', is4B, '0', '0', '0', '0', '0', '0', NONE, '0', '0'), -- stwx

5
execute1.vhdl
View File

@@ -753,6 +753,11 @@ begin
lv.xerc := v.e.xerc; lv.xerc := v.e.xerc;
lv.reserve := e_in.reserve; lv.reserve := e_in.reserve;
lv.rc := e_in.rc; lv.rc := e_in.rc;
-- decode l*cix and st*cix instructions here
if e_in.insn(31 downto 26) = "011111" and e_in.insn(10 downto 9) = "11" and
e_in.insn(5 downto 1) = "10101" then
lv.ci := '1';
end if;
-- Update registers -- Update registers
rin <= v; rin <= v;

3
loadstore1.vhdl
View File

@@ -209,6 +209,7 @@ begin
v.xerc := l_in.xerc; v.xerc := l_in.xerc;
v.reserve := l_in.reserve; v.reserve := l_in.reserve;
v.rc := l_in.rc; v.rc := l_in.rc;
v.nc := l_in.ci;
-- XXX Temporary hack. Mark the op as non-cachable if the address -- XXX Temporary hack. Mark the op as non-cachable if the address
-- is the form 0xc------- -- is the form 0xc-------
@@ -218,8 +219,6 @@ begin
-- bit otherwise. -- bit otherwise.
if lsu_sum(31 downto 28) = "1100" then if lsu_sum(31 downto 28) = "1100" then
v.nc := '1'; v.nc := '1';
else
v.nc := '0';
end if; end if;
-- Do length_to_sel and work out if we are doing 2 dwords -- Do length_to_sel and work out if we are doing 2 dwords