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Optimize more Dfg peephole patterns (#7423)

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Geza Lore 2026-04-14 16:22:54 +01:00 committed by GitHub
parent 7e3400b37d
commit ab0264deca
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5 changed files with 546 additions and 408 deletions
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907
src/V3DfgPeephole.cpp
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File diff suppressed because it is too large Load Diff

24
src/V3DfgPeepholePatterns.h
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@ -27,12 +27,12 @@
// Enumeration of each peephole optimization. Must be kept in sorted order (enforced by tests).
// clang-format off
#define FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION(macro) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_ASSOC_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_ASSOC_BINARY_LHS_OF_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_ASSOC_BINARY_RHS_OF_LHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_MUX_FROM_ONES) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_MUX_FROM_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_REPLICATE) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SEL) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SELF_EQ) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SELF_GT) \
@ -68,16 +68,19 @@
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, PUSH_SEL_THROUGH_SPLICE) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, PUSH_SHIFTL_THROUGH_COND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, PUSH_SHIFTR_THROUGH_COND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_ACI_BINARY_LHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_ACI_BINARY_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_ADD_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_AND_WITH_ONES) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_AND_WITH_SELF) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_CONCAT_OF_ADJOINING_SELS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_COND_WITH_BRANCHES_SAME) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_COND_WITH_FALSE_CONDITION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_COND_WITH_TRUE_CONDITION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_EQ_BIT_1) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_FULL_WIDTH_SEL) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_IDEMPOTENT_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_NEQ_BIT_0) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_NOT_NOT) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_OR_WITH_SELF) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_OR_WITH_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_REDUNDANT_ZEXT_ON_RHS_OF_SHIFT) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REMOVE_REPLICATE_ONCE) \
@ -92,13 +95,19 @@
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_ADD_WITH_COUNT_ONES) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_AND_OF_NOT_AND_NEQ) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_AND_OF_NOT_AND_NOT) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_AND_REP_COND_ELSE_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_AND_WITH_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_BITWISE_OF_REDUCTION_OF_SELS_WITH_REDUCTION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_BITWISE_OF_SELS_WITH_REDUCTION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONCAT_SAME) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONCAT_SAME_REP_ON_LHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONCAT_SAME_REP_ON_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONCAT_SEL_BOTTOM_AND_ZERO_WITH_SHIFTL) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONCAT_ZERO_AND_SEL_TOP_WITH_SHIFTR) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_CONST_ONES_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_CONST_ONE_ZERO) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_CONST_ZERO_ONE) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_CONST_ZERO_ONES) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_DEC) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_INC) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_OR_THEN_COND_LHS) \
@ -107,6 +116,8 @@
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_SAME_CAT_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_SAME_COND_ELSE) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_SAME_COND_THEN) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_THEN_OR_LHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_THEN_OR_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_WITH_ELSE_BRANCH_COND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_WITH_ELSE_BRANCH_ONES) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_COND_WITH_ELSE_BRANCH_ZERO) \
@ -116,10 +127,12 @@
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONTRADICTORY_AND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_CONTRADICTORY_AND_3) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_DISTRIBUTIVE_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_EQ_BIT_0) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_EXTEND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_LOGAND_WITH_AND) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_LOGOR_WITH_OR) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_MUX_WITH_SEL) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NEQ_BIT_1) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NESTED_CONCAT_OF_ADJOINING_SELS_ON_LHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NESTED_CONCAT_OF_ADJOINING_SELS_ON_RHS) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NOT_EQ) \
@ -149,10 +162,7 @@
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, RIGHT_LEANING_ASSOC) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_COND_WITH_NEQ_CONDITION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_COND_WITH_NOT_CONDITION) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_CONST_IN_COMMUTATIVE_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_NOT_IN_COMMUTATIVE_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_SAME_IN_COMMUTATIVE_BINARY) \
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_SIDE_IN_COMMUTATIVE_BINARY)
_FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, SWAP_SIDES_IN_BINARY)
// clang-format on
class VDfgPeepholePattern final {

17
test_regress/t/t_dfg_peephole.v
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@ -125,7 +125,8 @@ module t (
`signal(SWAP_VAR_IN_COMMUTATIVE_BINARY, rand_b + rand_a);
`signal(PUSH_BITWISE_OP_THROUGH_CONCAT, 32'h12345678 ^ {8'h0, rand_a[23:0]});
`signal(PUSH_BITWISE_OP_THROUGH_CONCAT_2, 32'h12345678 ^ {rand_b[7:0], rand_a[23:0]});
`signal(PUSH_COMPARE_OP_THROUGH_CONCAT, 4'b1011 == {2'b10, rand_a[1:0]});
`signal(PUSH_COMPARE_OP_THROUGH_CONCAT_EQ, 4'b1011 == {2'b10, rand_a[1:0]});
`signal(PUSH_COMPARE_OP_THROUGH_CONCAT_NE, 4'b1011 != {2'b10, rand_a[1:0]});
`signal(PUSH_REDUCTION_THROUGH_COND_WITH_CONST_BRANCH, |(rand_a[32] ? rand_a[3:0] : 4'h0));
`signal(REPLACE_REDUCTION_OF_CONST_AND, &const_a);
`signal(REPLACE_REDUCTION_OF_CONST_OR, |const_a);
@ -251,6 +252,8 @@ module t (
`signal(REPLACE_COND_CONST_ONE_ZERO, rand_a[0] ? 8'b1 : 8'b0);
`signal(REPLACE_COND_CONST_ZERO_ONE, rand_a[0] ? 8'b0 : 8'b1);
`signal(REPLACE_COND_CONST_ONES_ZERO, rand_a[0] ? 8'hff : 8'b0);
`signal(REPLACE_COND_CONST_ZERO_ONAE, rand_a[0] ? 8'b0 : 8'hff);
`signal(REPLACE_COND_CAT_LHS_CONST_ONE_ZERO, rand_a[0] ? {8'b1, rand_b[0]} : {8'b0, rand_b[1]});
`signal(REPLACE_COND_CAT_LHS_CONST_ZERO_ONE, rand_a[0] ? {8'b0, rand_b[0]} : {8'b1, rand_b[1]});
`signal(REPLACE_COND_SAME_CAT_LHS, rand_a[0] ? {8'd0, rand_b[0]} : {8'd0, rand_b[1]});
@ -310,6 +313,18 @@ module t (
`signal(FOLD_MUX_FROM_ONES, ones[rand_a[5:0]]);
`signal(FOLD_MUX_FROM_ZERO, zero[rand_a[5:0]]);
`signal(REPLACE_MUX_WITH_SEL, rand_a[const_a[5:0]]);
`signal(REPLACE_COND_THEN_OR_LHS, rand_a[0] ? rand_a[1] | rand_b[1] : rand_a[1]);
`signal(REPLACE_COND_THEN_OR_RHS, rand_a[0] ? rand_a[1] | rand_b[1] : rand_b[1]);
`signal(REMOVE_ACI_BINARY_LHS, ~rand_a & (~rand_b & ~rand_a));
`signal(REMOVE_ACI_BINARY_RHS, (~rand_b & ~rand_a) & ~rand_a);
`signal(REPLACE_CONCAT_SAME, {rand_a, rand_a});
`signal(REPLACE_CONCAT_REP_ON_LHS, {{2{rand_a}}, rand_a});
`signal(REPLACE_CONCAT_REP_ON_RHS, {rand_a, {2{rand_a}}});
`signal(REPLACE_AND_REP_COND_ELSE_ZERO, {4{rand_a[0]}} & (rand_a[1] ? rand_b[3:0] : 4'd0));
`signal(REPLACE_EQ_BIT_0, 1'b0 == rand_a[0]);
`signal(REMOVE_EQ_BIT_1, 1'b1 == rand_a[0]);
`signal(REMOVE_NEQ_BIT_0, 1'b0 != rand_a[0]);
`signal(REPLACE_NEQ_BIT_1, 1'b1 != rand_a[0]);
// Operators that should work wiht mismatched widths
`signal(MISMATCHED_ShiftL,const_a << 4'd2);

4
test_regress/t/t_dfg_stats_patterns.out
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@ -91,8 +91,8 @@ DFG patterns with depth 3
DFG patterns with depth 4
1 (CONCAT (REDXOR (AND (NOT _:A/a):B*/a (NOT _:C/a):D*/a):E*/a):F/1 (CONCAT (REDXOR (AND _:D*/a _:G*/a):H/a):I/1 (CONCAT (REDXOR _:J/a):K/1 (CONCAT _:L/1 _:M/b):N/c):O/d):P/e):Q/f
1 (CONCAT (REDXOR (AND (NOT _:A/a):B*/a (NOT _:C/a):D*/a):E/a):F/1 (CONCAT (REDXOR (AND _:G*/a _:D*/a):H/a):I/1 (CONCAT (SEL@0 _:J*/a):K/1 (CONCAT _:L/1 _:M/b):N/c):O/d):P/e):Q/f
1 (CONCAT (REDXOR (AND (NOT _:A/a):B*/a (NOT _:C/a):D*/a):E/a):F/1 (CONCAT (SEL@0 (AND _:B*/a _:G*/a):H*/a):I/1 (CONCAT (REDXOR _:J*/b):K/1 (CONCAT _:L/1 _:M/c):N/d):O/e):P/b):Q/f
1 (CONCAT (REDXOR (AND (NOT _:A/a):B*/a (NOT _:C/a):D*/a):E/a):F/1 (CONCAT (REDXOR (AND _:D*/a _:G*/a):H/a):I/1 (CONCAT (SEL@0 _:J*/a):K/1 (CONCAT _:L/1 _:M/b):N/c):O/d):P/e):Q/f
1 (CONCAT (REDXOR (AND (NOT _:A/a):B*/a (NOT _:C/a):D*/a):E/a):F/1 (CONCAT (SEL@0 (AND _:D*/a _:G*/a):H*/a):I/1 (CONCAT (REDXOR _:J*/b):K/1 (CONCAT _:L/1 _:M/c):N/d):O/e):P/b):Q/f
1 (CONCAT (REDXOR (REPLICATE (NOT _:A*/a):B/a cA:C/a):D*/b):E/1 (CONCAT (REDXOR (SEL@0 _:D*/b):F/c):G/1 (REDXOR (REPLICATE _:A*/a cA:H/a):I/b):J*/1):K/d):L/e
1 (CONCAT (REDXOR (REPLICATE (REPLICATE _:A*/a cA:B/b):C*/b cA:D/b):E/c):F*/1 (CONCAT (REDXOR (REPLICATE _:G/b cA:H/b):I*/c):J/1 (CONCAT (REDXOR _:K/d):L/1 (REDXOR _:E/c):F*/1):M/e):N/f):O/g
1 (CONCAT (REDXOR (REPLICATE (REPLICATE _:A*/a cA:B/b):C*/c cA:D/b):E*/b):F/1 (CONCAT (REDXOR (REPLICATE _:E*/b cA:G/b):H/d):I*/1 (CONCAT (REDXOR _:J*/d):K/1 (CONCAT _:L/1 _:I*/1):M/e):N/f):O/g):P/h

2
test_regress/t/t_opt_const_dfg.py
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@ -18,7 +18,7 @@ test.compile(verilator_flags2=["-Wno-UNOPTTHREADS", "--stats", test.pli_filename
test.execute()
if test.vlt:
test.file_grep(test.stats, r'Optimizations, Const bit op reduction\s+(\d+)', 43)
test.file_grep(test.stats, r'Optimizations, Const bit op reduction\s+(\d+)', 41)
test.file_grep(test.stats, r'SplitVar, packed variables split automatically\s+(\d+)', 1)
test.passes()