Don't use StringFormat for SPIR-V GetRawName

renderdoc/driver/shaders/spirv/spirv_debug.cpp

@@ -211,7 +211,7 @@ void ThreadState::EnterFunction(const rdcarray<Id> &arguments)
     OpVariable decl(it);
 
     ShaderVariable &stackvar = frame->locals[i];
-    stackvar.name = debugger.GetRawName(decl.result);
+    stackvar.name = GetRawName(decl.result);
 
     rdcstr sourceName = debugger.GetHumanName(decl.result);
 
@@ -342,7 +342,7 @@ void ThreadState::SetDst(Id id, const ShaderVariable &val)
     m_State->flags |= ShaderEvents::GeneratedNanOrInf;
 
   ids[id] = val;
-  ids[id].name = debugger.GetRawName(id);
+  ids[id].name = GetRawName(id);
 
   lastWrite[id] = m_State ? m_State->stepIndex : nextInstruction;
 
@@ -545,7 +545,7 @@ bool ThreadState::ReferencePointer(Id id)
   {
     StackFrame *frame = callstack.back();
 
-    rdcstr name = debugger.GetRawName(id);
+    rdcstr name = GetRawName(id);
 
     // see if this is a local variable which is newly referenced, if so add source vars for it
     for(size_t i = 0; i < frame->locals.size(); i++)

renderdoc/driver/shaders/spirv/spirv_debug.h

@@ -329,6 +329,9 @@ struct LocalMapping
   rdcarray<uint32_t> indexes;
 };
 
+Id ParseRawName(const rdcstr &name);
+rdcstr GetRawName(Id id);
+
 class Debugger : public Processor, public ShaderDebugger
 {
 public:
@@ -354,7 +357,6 @@ public:
   bool IsDebugExtInstSet(Id id) const;
   bool HasDebugInfo() const { return m_DebugInfo.valid; }
   bool InDebugScope(uint32_t inst) const;
-  rdcstr GetRawName(Id id) const;
   rdcstr GetHumanName(Id id);
   void AddSourceVars(rdcarray<SourceVariableMapping> &sourceVars, const ShaderVariable &var, Id id);
   void AllocateVariable(Id id, Id typeId, ShaderVariable &outVar);
@@ -393,8 +395,6 @@ private:
                                            uint64_t, const rdcstr &)>
                             callback) const;
 
-  static Id ParseRawName(const rdcstr &name);
-
   void MakeSignatureNames(const rdcarray<SPIRVInterfaceAccess> &sigList, rdcarray<rdcstr> &sigNames);
 
   /////////////////////////////////////////////////////////

renderdoc/driver/shaders/spirv/spirv_debug_setup.cpp

@@ -114,6 +114,42 @@ static const void *VarElemPointer(const ShaderVariable &var, uint32_t comp)
 
 namespace rdcspv
 {
+rdcstr GetRawName(Id id)
+{
+  // 32-bit value means at most 10 decimal digits, plus a preceeding _, plus trailing NULL.
+  char name[12] = {};
+  char *ptr = name + 10;
+  uint32_t val = id.value();
+  do
+  {
+    *ptr = char('0' + (val % 10));
+    ptr--;
+    val /= 10;
+  } while(val);
+
+  *ptr = '_';
+
+  return ptr;
+}
+
+Id ParseRawName(const rdcstr &name)
+{
+  if(name[0] != '_')
+    return Id();
+
+  uint32_t val = 0;
+  for(int i = 1; i < name.count(); i++)
+  {
+    if(name[i] < '0' || name[i] > '9')
+      return Id();
+
+    val *= 10;
+    val += uint32_t(name[i] - '0');
+  }
+
+  return Id::fromWord(val);
+}
+
 void AssignValue(ShaderVariable &dst, const ShaderVariable &src)
 {
   dst.value = src.value;
@@ -2270,29 +2306,6 @@ void Debugger::WriteThroughPointer(const ShaderVariable &ptr, const ShaderVariab
   }
 }
 
-rdcstr Debugger::GetRawName(Id id) const
-{
-  return StringFormat::Fmt("_%u", id.value());
-}
-
-Id Debugger::ParseRawName(const rdcstr &name)
-{
-  if(name[0] != '_')
-    return Id();
-
-  uint32_t val = 0;
-  for(int i = 1; i < name.count(); i++)
-  {
-    if(name[i] < '0' || name[i] > '9')
-      return Id();
-
-    val *= 10;
-    val += uint32_t(name[i] - '0');
-  }
-
-  return Id::fromWord(val);
-}
-
 rdcstr Debugger::GetHumanName(Id id)
 {
   // see if we have a dynamic name assigned (to disambiguate), if so use that
@@ -3353,3 +3366,35 @@ void Debugger::RegisterOp(Iter it)
 }
 
 };    // namespace rdcspv
+
+#if ENABLED(ENABLE_UNIT_TESTS)
+
+#include "catch/catch.hpp"
+
+TEST_CASE("Check SPIRV Id naming", "[tostr]")
+{
+  SECTION("Test GetRawName")
+  {
+    CHECK(rdcspv::GetRawName(rdcspv::Id::fromWord(1234)) == "_1234");
+    CHECK(rdcspv::GetRawName(rdcspv::Id::fromWord(12345)) == "_12345");
+    CHECK(rdcspv::GetRawName(rdcspv::Id::fromWord(999)) == "_999");
+    CHECK(rdcspv::GetRawName(rdcspv::Id::fromWord(0xffffffff)) == "_4294967295");
+    CHECK(rdcspv::GetRawName(rdcspv::Id()) == "_0");
+  };
+
+  SECTION("Test ParseRawName")
+  {
+    CHECK(rdcspv::ParseRawName("_1234") == rdcspv::Id::fromWord(1234));
+    CHECK(rdcspv::ParseRawName("_12345") == rdcspv::Id::fromWord(12345));
+    CHECK(rdcspv::ParseRawName("_999") == rdcspv::Id::fromWord(999));
+    CHECK(rdcspv::ParseRawName("_4294967295") == rdcspv::Id::fromWord(0xffffffff));
+    CHECK(rdcspv::ParseRawName("_0") == rdcspv::Id());
+    CHECK(rdcspv::ParseRawName("1234") == rdcspv::Id());
+    CHECK(rdcspv::ParseRawName("999") == rdcspv::Id());
+    CHECK(rdcspv::ParseRawName("1") == rdcspv::Id());
+    CHECK(rdcspv::ParseRawName("-1234") == rdcspv::Id());
+    CHECK(rdcspv::ParseRawName("asdf") == rdcspv::Id());
+  };
+}
+
+#endif