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Support const left shifts #310

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Support const left shifts #310

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712ea0e
Add shared const opcode definitions
guosran Jun 25, 2026
edbc506
Support const left shifts
guosran Jun 25, 2026
1162cba
Explain const shift operation
guosran Jul 16, 2026
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17 changes: 17 additions & 0 deletions fu/single/ShifterRTL.py
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Original file line number Diff line number Diff line change
Expand Up @@ -72,6 +72,23 @@ def comb_logic():
s.recv_in[s.in1_idx].rdy @= s.recv_all_val & s.send_out[0].rdy
s.recv_opt.rdy @= s.recv_all_val & s.send_out[0].rdy

elif s.recv_opt.msg.operation == OPT_LLS_CONST:
# Const shift uses the const queue for a fixed shift amount, avoiding
# a second dynamic operand. Example: payload=3, const=2 => 12; the
# output predicate still requires both the input and const predicates.
# Shift amount comes from the per-tile const queue. This is used by
# generated address arithmetic where the value is dataflow input but
# the left-shift amount is a static kernel constant.
s.send_out[0].msg.payload @= s.recv_in[s.in0_idx].msg.payload << s.recv_const.msg.payload
s.send_out[0].msg.predicate @= s.recv_in[s.in0_idx].msg.predicate & \
s.recv_const.msg.predicate & \
s.reached_vector_factor
s.recv_all_val @= s.recv_in[s.in0_idx].val & s.recv_const.val
s.send_out[0].val @= s.recv_all_val
s.recv_in[s.in0_idx].rdy @= s.recv_all_val & s.send_out[0].rdy
s.recv_const.rdy @= s.recv_all_val & s.send_out[0].rdy
s.recv_opt.rdy @= s.recv_all_val & s.send_out[0].rdy

elif s.recv_opt.msg.operation == OPT_LRS:
s.send_out[0].msg.payload @= s.recv_in[s.in0_idx].msg.payload >> s.recv_in[s.in1_idx].msg.payload
s.send_out[0].msg.predicate @= s.recv_in[s.in0_idx].msg.predicate & \
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48 changes: 48 additions & 0 deletions lib/opt_type.py
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Original file line number Diff line number Diff line change
Expand Up @@ -115,6 +115,46 @@
OPT_GEP_CONST = OpCodeType( 89 )
OPT_GEP_2D = OpCodeType( 90 )
OPT_GEP_2D_CONST = OpCodeType( 91 )
OPT_GRT_ONCE_CONST = OpCodeType( 92 )
OPT_GTE_CONST = OpCodeType( 93 )
OPT_LT_CONST = OpCodeType( 94 )
OPT_GT_CONST = OpCodeType( 95 )
OPT_REM_CONST = OpCodeType( 96 )
OPT_AND_CONST = OpCodeType( 97 )
OPT_OR_CONST = OpCodeType( 98 )
OPT_LLS_CONST = OpCodeType( 99 )

OPT_USES_CONST_LIST = (
OPT_CONST,
OPT_ADD_CONST,
OPT_SUB_CONST,
OPT_DIV_CONST,
OPT_EQ_CONST,
OPT_NE_CONST,
OPT_PHI_CONST,
OPT_LD_CONST,
OPT_STR_CONST,
OPT_MUL_CONST,
OPT_MUL_CONST_ADD,
OPT_ADD_CONST_LD,
OPT_INC_NE_CONST_NOT_GRT,
OPT_FADD_CONST,
OPT_FMUL_CONST,
OPT_VEC_ADD_CONST,
OPT_VEC_SUB_CONST,
OPT_VEC_ADD_CONST_COMBINED,
OPT_VEC_SUB_CONST_COMBINED,
OPT_GRT_ONCE_CONST,
OPT_GTE_CONST,
OPT_LT_CONST,
OPT_GT_CONST,
OPT_AND_CONST,
OPT_OR_CONST,
OPT_LLS_CONST,
OPT_REM_CONST,
OPT_GEP_CONST,
OPT_GEP_2D_CONST,
)

OPT_SYMBOL_DICT = {
OPT_START : "(start)",
Expand Down Expand Up @@ -201,6 +241,14 @@
OPT_REM_INCLUSIVE_START : "(%st)",
OPT_DIV_INCLUSIVE_END : "(/ed)",
OPT_REM_INCLUSIVE_END : "(%ed)",
OPT_GRT_ONCE_CONST : "(grant_once')",
OPT_GTE_CONST : "(?>=')",
OPT_LT_CONST : "(?<')",
OPT_GT_CONST : "(?>')",
OPT_AND_CONST : "(&')",
OPT_OR_CONST : "(|')",
OPT_LLS_CONST : "(<<')",
OPT_REM_CONST : "(%')",

OPT_LOOP_CONTROL : "(loop_ctrl)",
OPT_STREAM_LD : "(streaming_ld)",
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