refactor(avm): no fake rows in main trace (#7823)

Needed for gas accounting.

There are some extra changes but it's the best I could split the PR.

PS: We do have repeated SLOADS/SSTORES which are kind of fake, but all
else should be good (modulo the stubbed gadgets that dont have a
selector).

barretenberg/cpp/format.sh

@@ -13,6 +13,12 @@ if [ "$1" == "staged" ]; then
     sed -i.bak 's/\r$//' $FILE && rm ${FILE}.bak
     git add $FILE
   done
+elif [ "$1" == "changed" ]; then
+  echo Formatting barretenberg changed files...
+  for FILE in $(git diff-index --diff-filter=d --relative --name-only HEAD | grep -e '\.\(cpp\|hpp\|tcc\)$'); do
+    clang-format-16 -i $FILE
+    sed -i.bak 's/\r$//' $FILE && rm ${FILE}.bak
+  done
 elif [ "$1" == "check" ]; then
   for FILE in $(find ./src -iname *.hpp -o -iname *.cpp -o -iname *.tcc | grep -v src/msgpack-c); do
     clang-format-16 --dry-run --Werror $FILE

barretenberg/cpp/pil/avm/main.pil

@@ -100,10 +100,11 @@ namespace main(256);
     da_out_of_gas * (1 - da_out_of_gas) = 0;
 
     // Constrain that the gas decrements correctly per instruction
+    // TODO: Special-case for external call.
     #[L2_GAS_REMAINING_DECREMENT]
-    sel_gas_accounting_active * (l2_gas_remaining' - l2_gas_remaining + l2_gas_op_cost) = 0;
+    sel_gas_accounting_active * (1 - sel_op_external_call) * (l2_gas_remaining' - l2_gas_remaining + l2_gas_op_cost) = 0;
     #[DA_GAS_REMAINING_DECREMENT]
-    sel_gas_accounting_active * (da_gas_remaining' - da_gas_remaining + da_gas_op_cost) = 0;
+    sel_gas_accounting_active * (1 - sel_op_external_call) * (da_gas_remaining' - da_gas_remaining + da_gas_op_cost) = 0;
 
     // Constrain that the remaining gas is unchanged otherwise (multi-line operations)
     #[L2_GAS_INACTIVE]
@@ -497,11 +498,11 @@ namespace main(256);
     //       Alternatively, we introduce a boolean selector for the three opcodes mentioned above.
     //       Note: External call gas cost is not constrained
     pol commit sel_gas_accounting_active;
-    pol commit sel_mem_op_activate_gas; // TODO: remove this one
     // TODO: remove sload and sstore from here
     // This temporarily disables gas tracking for sload and sstore because our gas
     // tracking doesn't work properly for instructions that span multiple rows
-    sel_gas_accounting_active - OPCODE_SELECTORS - SEL_ALL_CTRL_FLOW - sel_op_sload - sel_op_sstore - sel_mem_op_activate_gas = 0;
+    // TODO: disabling this until PR in stack.
+    // sel_gas_accounting_active - OPCODE_SELECTORS - SEL_ALL_CTRL_FLOW - sel_op_sload - sel_op_sstore - sel_mem_op_activate_gas = 0;
 
     // Program counter must increment if not jumping or returning
     // TODO: support for muli-rows opcode in execution trace such as

barretenberg/cpp/src/barretenberg/vm/avm/generated/circuit_builder.cpp

@@ -206,7 +206,6 @@ AvmCircuitBuilder::ProverPolynomials AvmCircuitBuilder::compute_polynomials() co
         polys.main_sel_gas_accounting_active[i] = rows[i].main_sel_gas_accounting_active;
         polys.main_sel_last[i] = rows[i].main_sel_last;
         polys.main_sel_mem_op_a[i] = rows[i].main_sel_mem_op_a;
-        polys.main_sel_mem_op_activate_gas[i] = rows[i].main_sel_mem_op_activate_gas;
         polys.main_sel_mem_op_b[i] = rows[i].main_sel_mem_op_b;
         polys.main_sel_mem_op_c[i] = rows[i].main_sel_mem_op_c;
         polys.main_sel_mem_op_d[i] = rows[i].main_sel_mem_op_d;

barretenberg/cpp/src/barretenberg/vm/avm/generated/circuit_builder.hpp

@@ -20,8 +20,8 @@ class AvmCircuitBuilder {
     using Polynomial = Flavor::Polynomial;
     using ProverPolynomials = Flavor::ProverPolynomials;
 
-    static constexpr size_t num_fixed_columns = 704;
-    static constexpr size_t num_polys = 704 + 74;
+    static constexpr size_t num_fixed_columns = 703;
+    static constexpr size_t num_polys = 703 + 74;
     std::vector<Row> rows;
 
     void set_trace(std::vector<Row>&& trace) { rows = std::move(trace); }