Fix comments in zapimage.cpp (#1629)

I noticed that base addresses in the comments were not correct (constants in the switches.h file had been updated without updating the comments in this file), and while at it, fixed spelling and grammar in other comments.

Author: AntonLapounov

src/coreclr/src/zap/zapimage.cpp

@@ -47,7 +47,7 @@ ZapImage::ZapImage(Zapper *zapper)
 ZapImage::~ZapImage()
 {
 #ifdef ZAP_HASHTABLE_TUNING
-    // If ZAP_HASHTABLE_TUNING is defined, preallocate is overloaded to print the tunning constants
+    // If ZAP_HASHTABLE_TUNING is defined, preallocate is overloaded to print the tuning constants
     Preallocate();
 #endif
 
@@ -339,10 +339,10 @@ void ZapImage::AllocateVirtualSections()
 
         m_pExternalMethodCellSection = NewVirtualSection(pDataSection, IBCProfiledSection | HotColdSortedRange | ExternalMethodThunkSection, TARGET_POINTER_SIZE);
 
-        // m_pStubDispatchCellSection is  deliberately placed  directly after
+        // m_pStubDispatchCellSection is deliberately placed directly after
         // the last m_pDelayLoadInfoTableSection (all .data sections go together in the order indicated).
         // We do this to place it as the last "hot, written" section.  Why? Because
-        // we don't split the dispatch cells into hot/cold sections (We probably should),
+        // we don't split the dispatch cells into hot/cold sections (we probably should),
         // and so the section is actually half hot and half cold.
         // But it turns out that the hot dispatch cells always come
         // first (because the code that uses them is hot and gets compiled first).
@@ -363,14 +363,14 @@ void ZapImage::AllocateVirtualSections()
         // Virtual sections that are moved to .cdata when we have profile data.
         //
 
-        // This is everyhing that is assumed to be warm in the first strata
+        // This is everything that is assumed to be warm in the first strata
         // of non-profiled scenarios.  MethodTables related to objects etc.
         m_pPreloadSections[CORCOMPILE_SECTION_WARM] = NewVirtualSection(pDataSection, IBCProfiledSection | WarmRange | EEDataSection, TARGET_POINTER_SIZE);
 
         m_pPreloadSections[CORCOMPILE_SECTION_RVA_STATICS_COLD] = NewVirtualSection(pDataSection, IBCProfiledSection | ColdRange | RVAStaticsSection);
 
         // In an ideal world these are cold in both profiled and the first strata
-        // of non-profiled scenarios (i.e. no reflection, etc. )  The sections at the
+        // of non-profiled scenarios (i.e. no reflection, etc.)  The sections at the
         // bottom correspond to further strata of non-profiled scenarios.
         m_pPreloadSections[CORCOMPILE_SECTION_CLASS_COLD] = NewVirtualSection(pDataSection, IBCProfiledSection | ColdRange | ClassSection, TARGET_POINTER_SIZE);
         m_pPreloadSections[CORCOMPILE_SECTION_CROSS_DOMAIN_INFO] = NewVirtualSection(pDataSection, IBCUnProfiledSection | ColdRange | CrossDomainInfoSection, TARGET_POINTER_SIZE);
@@ -517,7 +517,7 @@ void ZapImage::AllocateVirtualSections()
         m_pHotGCSection = NewVirtualSection(pTextSection, IBCProfiledSection | WarmRange | GCInfoSection, sizeof(DWORD));
 
 #if !defined(_TARGET_ARM_)
-        // For ARM, put these sections more towards the end because bl/b instructions have limited diplacement
+        // For ARM, put these sections more towards the end because bl/b instructions have limited displacement
 
         // IL
         m_pILSection  = NewVirtualSection(pTextSection, IBCProfiledSection | HotColdSortedRange | ILSection, sizeof(DWORD));
@@ -579,7 +579,7 @@ void ZapImage::AllocateVirtualSections()
         m_pColdCodeSection->SetDefaultFill(DEFAULT_CODE_BUFFER_INIT);
 
 #if defined(_TARGET_ARM_)
-        // For ARM, put these sections more towards the end because bl/b instructions have limited diplacement
+        // For ARM, put these sections more towards the end because bl/b instructions have limited displacement
 
         // IL
         m_pILSection  = NewVirtualSection(pTextSection, IBCProfiledSection | HotColdSortedRange | ILSection, sizeof(DWORD));
@@ -639,7 +639,7 @@ void ZapImage::Preallocate()
 {
     COUNT_T cbILImage = m_ModuleDecoder.GetSize();
 
-    // Curb the estimate to handle corner cases gracefuly
+    // Curb the estimate to handle corner cases gracefully
     cbILImage = min(cbILImage, 50000000);
 
     PREALLOCATE_HASHTABLE(ZapImage::m_CompiledMethods, 0.0050, cbILImage);
@@ -1019,7 +1019,7 @@ HANDLE ZapImage::GenerateFile(LPCWSTR wszOutputFileName, CORCOMPILE_NGEN_SIGNATU
         rsds.magic = VAL32(0x53445352); // "SDSR";
         rsds.age = 1;
         // our PDB signature will be the same as our NGEN signature.
-        // However we want the printed version of the GUID to be be the same as the
+        // However we want the printed version of the GUID to be the same as the
         // byte dump of the signature so we swap bytes to make this work.
         //
         // * See code:CCorSvcMgr::CreatePdb for where this is used.
@@ -1079,10 +1079,10 @@ HANDLE ZapImage::SaveImage(LPCWSTR wszOutputFileName, LPCWSTR wszDllPath, CORCOM
 
     OutputTables();
 
-    // Create a empty export table.  This makes tools like symchk not think
-    // that native images are resoure-only DLLs.  It is important to NOT
+    // Create an empty export table.  This makes tools like symchk not think
+    // that native images are resource-only DLLs.  It is important to NOT
     // be a resource-only DLL because those DLL's PDBS are not put up on the
-    // symbol server and we want NEN PDBS to be placed there.
+    // symbol server and we want NGEN PDBS to be placed there.
     ZapPEExports* exports = new(GetHeap()) ZapPEExports(wszDllPath);
     m_pDebugSection->Place(exports);
     SetDirectoryEntry(IMAGE_DIRECTORY_ENTRY_EXPORT, exports);
@@ -1232,7 +1232,7 @@ void ZapImage::CalculateZapBaseAddress()
                 baseAddress = 0x30000000;
 #elif defined(_TARGET_64BIT_)
                 // We use 04000000 for an exe
-                // which is remapped to 0x642`88000000 on x64
+                // which is remapped to 0x644`88000000 on x64
                 baseAddress = 0x04000000;
 #endif
             }
@@ -1243,14 +1243,14 @@ void ZapImage::CalculateZapBaseAddress()
                 baseAddress = 0x31000000;
 #elif defined(_TARGET_64BIT_)
                 // We start a 05000000 for the main assembly with the manifest
-                // which is remapped to 0x642`8A000000 on x64
+                // which is remapped to 0x644`8A000000 on x64
                 baseAddress = 0x05000000;
 #endif
             }
         }
         else // is dependent assembly of a multi-module assembly
         {
-            // Set the base address for a dependant multi module assembly
+            // Set the base address for a dependent multi-module assembly
 
             // We should have already set the nextBaseAddressForMultiModule
             // when we compiled the manifest module
@@ -1295,24 +1295,21 @@ void ZapImage::CalculateZapBaseAddress()
     nextBaseAddressForMultiModule = tempBaseAddress;
 
     //
-    // Now we remap the 32-bit address range used for x86 and PE32 images into thre
+    // Now we remap the 32-bit address range used for x86 and PE32 images into the
     // upper address range used on 64-bit platforms
     //
-#if USE_UPPER_ADDRESS
-#if defined(_TARGET_64BIT_)
+#if USE_UPPER_ADDRESS   // Implies _TARGET_64BIT_
     if (baseAddress < 0x80000000)
     {
         if (baseAddress < 0x40000000)
-            baseAddress += 0x40000000; // We map [00000000..3fffffff] to [642'80000000..642'ffffffff]
+            baseAddress += 0x40000000; // We map [00000000..3fffffff] to [644'80000000..644'ffffffff]
         else
-            baseAddress -= 0x40000000; // We map [40000000..7fffffff] to [642'00000000..642'7fffffff]
+            baseAddress -= 0x40000000; // We map [40000000..7fffffff] to [644'00000000..644'7fffffff]
 
         baseAddress *= UPPER_ADDRESS_MAPPING_FACTOR;
         baseAddress += CLR_UPPER_ADDRESS_MIN;
     }
 #endif
-#endif
-
 
     // Apply the calculated base address.
     SetBaseAddress(baseAddress);
@@ -1548,7 +1545,7 @@ void ZapImage::OutputTables()
     }
 
 #if defined(FEATURE_PAL) && !defined(_TARGET_64BIT_)
-    // To minimize wasted VA space on 32 bit systems align file to page bounaries (presumed to be 4K).
+    // To minimize wasted VA space on 32-bit systems, align file to page boundaries (presumed to be 4K).
     SetFileAlignment(0x1000);
 #elif defined(_TARGET_ARM_) && defined(FEATURE_CORESYSTEM)
     if (!IsReadyToRunCompilation())
@@ -1623,7 +1620,7 @@ void ZapImage::ProfileDisableInlining()
 }
 
 //  CompileHotRegion
-//     Performs the compilation and placement for all methods in the the "Hot" code region
+//     Performs the compilation and placement for all methods in the "Hot" code region
 //     Methods placed in this region typically correspond to all of the methods that were
 //     executed during any of the profiling scenarios.
 //
@@ -1663,7 +1660,7 @@ void ZapImage::CompileHotRegion()
             else if (TypeFromToken(token) == ibcMethodSpec)
             {
                 //
-                //  compile a generic/parameterized method
+                // Compile a generic/parameterized method
                 //
                 CORBBTPROF_BLOB_PARAM_SIG_ENTRY *pBlobSigEntry = pProfileData->GetBlobSigEntry(token);
 
@@ -1687,7 +1684,7 @@ void ZapImage::CompileHotRegion()
                     else
                     {
                         // This generic/parameterized method is not part of the native image
-                        // Either the IBC type  specified no longer exists or it is a SIMD types
+                        // Either the IBC type specified no longer exists or it is a SIMD types
                         // or the type can't be loaded in a ReadyToRun native image because of
                         // a cross-module type dependencies.
                         //
@@ -1711,7 +1708,7 @@ void ZapImage::CompileHotRegion()
 }
 
 //  CompileColdRegion
-//     Performs the compilation and placement for all methods in the the "Cold" code region
+//     Performs the compilation and placement for all methods in the "Cold" code region
 //     Methods placed in this region typically correspond to all of the methods that were
 //     NOT executed during any of the profiling scenarios.
 //
@@ -1906,7 +1903,7 @@ BOOL ZapImage::IsVTableGapMethod(mdMethodDef md)
     DWORD dwAttributes;
 
     // Get method attributes and check that RTSpecialName was set for the method (this means the name has
-    // semantic import to the runtime and must be formatted rigorously with one of a few well known rules).
+    // semantic import to the runtime and must be formatted rigorously with one of a few well-known rules).
     // Note that we just return false on any failure path since this will just lead to our caller continuing
     // to throw the exception they were about to anyway.
     hr = m_pMDImport->GetMethodDefProps(md, &dwAttributes);
@@ -1995,7 +1992,7 @@ ZapImage::CompileStatus ZapImage::TryCompileInstantiatedMethod(CORINFO_METHOD_HA
         return COMPILE_EXCLUDED;
 
     // If we compiling this method because it was specified by the IBC profile data
-    // then issue an warning if this method is not on our uncompiled method list
+    // then issue a warning if this method is not on our uncompiled method list.
     //
     if (methodProfilingDataFlags != 0)
     {
@@ -2061,7 +2058,7 @@ ZapImage::CompileStatus ZapImage::TryCompileMethodWorker(CORINFO_METHOD_HANDLE h
     //
     if (methodProfilingDataFlags != 0)
     {
-        // Report the profiling data flags for layout of the EE datastructures
+        // Report the profiling data flags for layout of the EE data structures
         m_pPreloader->SetMethodProfilingFlags(handle, methodProfilingDataFlags);
 
         // Hot methods can be marked to be excluded from the AOT native image.
@@ -2074,7 +2071,7 @@ ZapImage::CompileStatus ZapImage::TryCompileMethodWorker(CORINFO_METHOD_HANDLE h
         }
 
         // Cold methods can be marked to be excluded from the AOT native image.
-        // We can reduced the size of the AOT native image by selectively
+        // We can reduce the size of the AOT native image by selectively
         // excluding the code for some of the cold methods.
         //
         if ((methodProfilingDataFlags & (1 << ExcludeColdMethodCode)) != 0)
@@ -2084,7 +2081,7 @@ ZapImage::CompileStatus ZapImage::TryCompileMethodWorker(CORINFO_METHOD_HANDLE h
         }
 
         // If the code was never executed based on the profile data
-        // then don't compile this method now. Wait until until later
+        // then don't compile this method now. Wait until later
         // when we are compiling the methods in the cold section.
         //
         if ((methodProfilingDataFlags & (1 << ReadMethodCode)) == 0)
@@ -2167,9 +2164,9 @@ ZapImage::CompileStatus ZapImage::TryCompileMethodWorker(CORINFO_METHOD_HANDLE h
         //     messages to the console
         if (IsReadyToRunCompilation())
         {
-            // When compiling the method we may receive an exeception when the
+            // When compiling the method, we may receive an exception when the
             // method uses a feature that is Not Implemented for ReadyToRun
-            // or a Type Load exception if the method uses for a SIMD type.
+            // or a Type Load exception if the method uses a SIMD type.
             //
             // We skip the compilation of such methods and we don't want to
             // issue a warning or error
@@ -2186,7 +2183,7 @@ ZapImage::CompileStatus ZapImage::TryCompileMethodWorker(CORINFO_METHOD_HANDLE h
             ex->GetMessage(message);
 
             // FileNotFound errors here can be converted into a single error string per ngen compile,
-            //  and the detailed error is available with verbose logging
+            // and the detailed error is available with verbose logging
             if (hrException == COR_E_FILENOTFOUND)
             {
                 StackSString logMessage(W("System.IO.FileNotFoundException: "));
@@ -2575,7 +2572,7 @@ HRESULT ZapImage::parseProfileData()
         return S_FALSE;
     }
 
-    // This module has profile data (this ends up controling the layout of physical and virtual
+    // This module has profile data (this ends up controlling the layout of physical and virtual
     // sections within the image, see ZapImage::AllocateVirtualSections.
     m_fHaveProfileData = true;
     m_zapper->m_pOpt->m_fHasAnyProfileData = true;
@@ -2929,7 +2926,7 @@ HRESULT ZapImage::convertProfileDataFromV1()
                 sizeWrite += blobEntry->cBuffer;
                 if (blobEntry->blobType == ParamMethodSpec)
                 {
-                    sizeWrite -= 1;  // Adjust for
+                    sizeWrite -= 1;  // Adjust for ENCODE_METHOD_SIG prefix removal
                 }
                 sizeRead  += sizeof(CORBBTPROF_BLOB_ENTRY_V1);
                 sizeRead  += blobEntry->cBuffer;
@@ -3325,7 +3322,7 @@ void ZapImage::hashBBUpdateFlagsAndCompileResult(mdToken token, unsigned methodP
         assert(pEntry->md == newEntry.md);
         assert(pEntry->flags == 0);   // the flags should not be set at this point.
 
-        // Copy and keep the two fleids that were previously set
+        // Copy and keep the two fields that were previously set
         newEntry.size = pEntry->size;
         newEntry.pos = pEntry->pos;
     }
@@ -3447,15 +3444,15 @@ bool ZapImage::canIntraModuleDirectCall(
         goto CALL_VIA_ENTRY_POINT;
     }
 
-    // Does the methods's class have a cctor, etc?
+    // Does the method's class have a cctor, etc?
 
     if (!m_pPreloader->CanSkipMethodPreparation(callerFtn, targetFtn, pReason, accessFlags))
         goto CALL_VIA_ENTRY_POINT;
 
     ZapMethodHeader * pMethod;
     pMethod = GetCompiledMethod(targetFtn);
 
-    // If we have not compiled the method then we can't call direct
+    // If we have not compiled the method, then we can't call directly
 
     if (pMethod == NULL)
     {
@@ -3556,13 +3553,13 @@ void ZapImage::Error(mdToken token, HRESULT hr, UINT resID,  LPCWSTR message)
     // Some warnings are demoted to informational level
     if (resID == IDS_EE_SIMD_NGEN_DISALLOWED)
     {
-        // Supress printing of "Target-dependent SIMD vector types may not be used with ngen."
+        // Suppress printing of "Target-dependent SIMD vector types may not be used with ngen."
         level = CORZAP_LOGLEVEL_INFO;
     }
 
     if (resID == IDS_EE_HWINTRINSIC_NGEN_DISALLOWED)
     {
-        // Supress printing of "Hardware intrinsics may not be used with ngen."
+        // Suppress printing of "Hardware intrinsics may not be used with ngen."
         level = CORZAP_LOGLEVEL_INFO;
     }
 
@@ -3574,7 +3571,7 @@ void ZapImage::Error(mdToken token, HRESULT hr, UINT resID,  LPCWSTR message)
         if (m_zapper->m_pOpt->m_ignoreErrors && !m_zapper->m_pOpt->m_verbose)
             return;
 
-        // Supress printing of "The generic type/method specified by the IBC data is not available to this assembly"
+        // Suppress printing of "The generic type/method specified by the IBC data is not available to this assembly"
         level = CORZAP_LOGLEVEL_INFO;
     }
 #endif