Fix vpi_handle_by_name generated scope retrieval (#7187 repair) (#7214)

Co-authored-by: Christian Hecken <christian.hecken@ibm.com>

include/verilated_vpi.cpp

@@ -2233,11 +2233,6 @@ static bool vl_vpi_parse_indices(std::string& name, std::vector<PLI_INT32>& indi
                                  VlVpiBitRange* bitRange = nullptr) {
     if (name.empty() || name.back() != ']') return false;
 
-    // Collapse consecutive spaces into single spaces
-    name.erase(
-        std::unique(name.begin(), name.end(), [](char a, char b) { return a == ' ' && b == ' '; }),
-        name.end());
-
     // Only parse brackets after the last escaped identifier's terminating space
     size_t escapeSpacePos = std::string::npos;
     const size_t backslashPos = name.rfind('\\');
@@ -2307,12 +2302,16 @@ vpiHandle vpi_handle_by_name(PLI_BYTE8* namep, vpiHandle scope) {
     if (VL_UNLIKELY(!namep)) return nullptr;
     VL_DEBUG_IF_PLI(VL_DBG_MSGF("- vpi: vpi_handle_by_name %s %p\n", namep, scope););
 
-    // Parse any array indices and optional bit range from the name
-    // e.g., "mem[0][3][2]" or "signal[15:8]" or "mem[0][3][15:8]"
     std::string scopeAndName = namep;
+
+    // Collapse consecutive spaces into single spaces (can occur with escaped identifiers)
+    scopeAndName.erase(std::unique(scopeAndName.begin(), scopeAndName.end(),
+                                   [](char a, char b) { return a == ' ' && b == ' '; }),
+                       scopeAndName.end());
+
     static thread_local std::vector<PLI_INT32> indices;
     VlVpiBitRange bitRange;
-    const bool hasIndices = vl_vpi_parse_indices(scopeAndName, indices, &bitRange);
+    bool hasIndices = false;
 
     const VerilatedVar* varp = nullptr;
     const VerilatedScope* scopep;
@@ -2328,6 +2327,9 @@ vpiHandle vpi_handle_by_name(PLI_BYTE8* namep, vpiHandle scope) {
     {
         // This doesn't yet follow the hierarchy in the proper way
         bool isPackage = false;
+
+        // Scopes in generate blocks can also end with an index, so look it up first before
+        // interpreting the trailing brackets as array indices or bit selects.
         scopep = Verilated::threadContextp()->scopeFind(scopeAndName.c_str());
         if (scopep) {  // Whole thing found as a scope
             if (scopep->type() == VerilatedScope::SCOPE_MODULE) {
@@ -2367,6 +2369,11 @@ vpiHandle vpi_handle_by_name(PLI_BYTE8* namep, vpiHandle scope) {
             scopename = scopeAndName.substr(0, pos);
             if (scopename == "$unit") scopename = "\\$unit ";
         }
+
+        // Parse any array indices and optional bit range from the name
+        // e.g., "mem[0][3][2]" or "signal[15:8]" or "mem[0][3][15:8]"
+        hasIndices = vl_vpi_parse_indices(basename, indices, &bitRange);
+
         if (prevpos == std::string::npos) {
             // scopename is a toplevel (no '.' separator), so search in our TOP ports first.
             scopep = Verilated::threadContextp()->scopeFind("TOP");

test_regress/t/t_vpi_var.cpp

@@ -9,6 +9,7 @@
 //
 //*************************************************************************
 
+#include "vpi_user.h"
 #ifdef IS_VPI
 
 #include "sv_vpi_user.h"
@@ -1215,6 +1216,38 @@ int _mon_check_multi_index() {
         CHECK_RESULT(vpi_get(vpiSize, vh_two_escapes_ps), 4);
     }
 
+    // vpi_handle_by_name with generated signal
+    {
+        // Retrieve signal
+        TestVpiHandle vh_generated = vpi_handle_by_name((PLI_BYTE8*)"t.gen[0].gen_sig", NULL);
+        CHECK_RESULT_NZ(vh_generated);
+        CHECK_RESULT(vpi_get(vpiType, vh_generated), vpiReg);
+        CHECK_RESULT(vpi_get(vpiSize, vh_generated), 8);
+        vpi_get_value(vh_generated, &v);
+        CHECK_RESULT(v.value.integer, 0xAB);
+
+        // Single bit indexing
+        TestVpiHandle vh_generated_bit
+            = vpi_handle_by_name((PLI_BYTE8*)"t.gen[0].gen_sig[3]", NULL);
+        CHECK_RESULT_NZ(vh_generated_bit);
+        CHECK_RESULT(vpi_get(vpiType, vh_generated_bit), vpiReg);
+        CHECK_RESULT(vpi_get(vpiSize, vh_generated_bit), 1);
+        vpi_get_value(vh_generated_bit, &v);
+        CHECK_RESULT(v.value.integer, 1);
+
+        // Generated scope
+        TestVpiHandle vh_generated_scope = vpi_handle_by_name((PLI_BYTE8*)"t.subs[1]", NULL);
+        CHECK_RESULT_NZ(vh_generated_scope);
+        CHECK_RESULT(vpi_get(vpiType, vh_generated_scope), vpiGenScope);
+
+        // Signal in generated instance
+        TestVpiHandle vh_generated_inst
+            = vpi_handle_by_name((PLI_BYTE8*)"t.subs[1].subsub.subsig1", NULL);
+        CHECK_RESULT_NZ(vh_generated_inst);
+        CHECK_RESULT(vpi_get(vpiType, vh_generated_inst), vpiReg);
+        CHECK_RESULT(vpi_get(vpiSize, vh_generated_inst), 1);
+    }
+
     // vpi_handle_by_name with array indexing
     {
         TestVpiHandle vh_1d = vpi_handle_by_name((PLI_BYTE8*)"t.quads[2]", nullptr);

test_regress/t/t_vpi_var.v

@@ -76,6 +76,12 @@ extern "C" int mon_check();
 
    logic [31:0] some_mem [4] /* verilator public_flat_rd */ = {0, 0, 0, 432};
 
+   generate
+     for (genvar i = 0; i < 1; i++) begin : gen
+       wire [7:0] gen_sig /*verilator public_flat_rw*/ = 8'hAB;
+     end
+   endgenerate
+
    sub sub();
 
    // Test loop

test_regress/t/t_vpi_var2.v

@@ -94,6 +94,12 @@ extern "C" int mon_check();
    logic [31:0] some_mem [4] = {0, 0, 0, 432};
 /*verilator public_off*/
 
+   generate
+     for (genvar i = 0; i < 1; i++) begin : gen
+       wire [7:0] gen_sig /*verilator public_flat_rw*/ = 8'hAB;
+     end
+   endgenerate
+
    sub sub();
 
    // Test loop

test_regress/t/t_vpi_var3.v

@@ -74,6 +74,12 @@ extern "C" int mon_check();
    localparam int nullptr = 123;
    logic [31:0] some_mem [4] = {0, 0, 0, 432};
 
+   generate
+     for (genvar i = 0; i < 1; i++) begin : gen
+       wire [7:0] gen_sig /*verilator public_flat_rw*/ = 8'hAB;
+     end
+   endgenerate
+
    sub sub();
 
    // Test loop