Fix New Coverity Scan Warning

Coverity Scan warned about logically dead code, because index >= 0 && index
< NReal can never be true if NReal is 0.

Src/Particle/AMReX_StructOfArrays.H

@@ -42,10 +42,16 @@ struct StructOfArrays {
  */
  [[nodiscard]] RealVector& GetRealData (const int index) {
  AMREX_ASSERT(index >= 0 && index < NReal + static_cast<int>(m_runtime_rdata.size()));
- if (index >= 0 && index < NReal) return m_rdata[index];
- else {
+ if constexpr (NReal == 0) {
  AMREX_ASSERT(m_defined);
- return m_runtime_rdata[index - NReal];
+ return m_runtime_rdata[index];
+ } else {
+ if (index < NReal) {
+ return m_rdata[index];
+ } else {
+ AMREX_ASSERT(m_defined);
+ return m_runtime_rdata[index - NReal];
+ }
  }
  }
 
@@ -55,10 +61,16 @@ struct StructOfArrays {
  */
  [[nodiscard]] const RealVector& GetRealData (const int index) const {
  AMREX_ASSERT(index >= 0 && index < NReal + static_cast<int>(m_runtime_rdata.size()));
- if (index >= 0 && index < NReal) return m_rdata[index];
- else {
+ if constexpr (NReal == 0) {
  AMREX_ASSERT(m_defined);
- return m_runtime_rdata[index - NReal];
+ return m_runtime_rdata[index];
+ } else {
+ if (index < NReal) {
+ return m_rdata[index];
+ } else {
+ AMREX_ASSERT(m_defined);
+ return m_runtime_rdata[index - NReal];
+ }
  }
  }
 
@@ -68,10 +80,16 @@ struct StructOfArrays {
  */
  [[nodiscard]] IntVector& GetIntData (const int index) {
  AMREX_ASSERT(index >= 0 && index < NInt + static_cast<int>(m_runtime_idata.size()));
- if (index >= 0 && index < NInt) return m_idata[index];
- else {
+ if constexpr (NInt == 0) {
  AMREX_ASSERT(m_defined);
- return m_runtime_idata[index - NInt];
+ return m_runtime_idata[index];
+ } else {
+ if (index < NInt) {
+ return m_idata[index];
+ } else {
+ AMREX_ASSERT(m_defined);
+ return m_runtime_idata[index - NInt];
+ }
  }
  }
 
@@ -82,10 +100,16 @@ struct StructOfArrays {
  */
  [[nodiscard]] const IntVector& GetIntData (const int index) const {
  AMREX_ASSERT(index >= 0 && index < NInt + static_cast<int>(m_runtime_idata.size()));
- if (index >= 0 && index < NInt) return m_idata[index];
- else {
+ if constexpr (NInt == 0) {
  AMREX_ASSERT(m_defined);
- return m_runtime_idata[index - NInt];
+ return m_runtime_idata[index];
+ } else {
+ if (index < NInt) {
+ return m_idata[index];
+ } else {
+ AMREX_ASSERT(m_defined);
+ return m_runtime_idata[index - NInt];
+ }
  }
  }
 
@@ -148,8 +172,12 @@ struct StructOfArrays {
 
  void resize (size_t count)
  {
- for (int i = 0; i < NReal; ++i) m_rdata[i].resize(count);
- for (int i = 0; i < NInt; ++i) m_idata[i].resize(count);
+ if constexpr (NReal > 0) {
+ for (int i = 0; i < NReal; ++i) { m_rdata[i].resize(count); }
+ }
+ if constexpr (NInt > 0) {
+ for (int i = 0; i < NInt; ++i) { m_idata[i].resize(count); }
+ }
  for (int i = 0; i < int(m_runtime_rdata.size()); ++i) m_runtime_rdata[i].resize(count);
  for (int i = 0; i < int(m_runtime_idata.size()); ++i) m_runtime_idata[i].resize(count);
  }