JIT: Fix BBJ_COND-related assert in OptIfConversionDsc::IfConvertDump (…

…#95934)

In #95773, I incorrectly assumed m_startBlock would always be a BBJ_COND in OptIfConversionDsc::IfConvertDump, but it can be converted to a BBJ_ALWAYS before being dumped, thus hitting an assert when m_startBlock->GetTrueTarget() is called. This is fixed by calling the correct target accessor method depending on the type of m_startBlock.

(Note that IfConvertDump is only called if dumps are enabled, hence why this assert wasn't initially hit in CI.)

src/coreclr/jit/ifconversion.cpp

@@ -381,15 +381,15 @@ void OptIfConversionDsc::IfConvertDump()
 {
     assert(m_startBlock != nullptr);
     m_comp->fgDumpBlock(m_startBlock);
-    for (BasicBlock* dumpBlock = m_startBlock->Next(); dumpBlock != m_finalBlock;
-         dumpBlock             = dumpBlock->GetUniqueSucc())
+    BasicBlock* dumpBlock = m_startBlock->KindIs(BBJ_COND) ? m_startBlock->GetFalseTarget() : m_startBlock->Next();
+    for (; dumpBlock != m_finalBlock; dumpBlock = dumpBlock->GetUniqueSucc())
     {
         m_comp->fgDumpBlock(dumpBlock);
     }
     if (m_doElseConversion)
     {
-        for (BasicBlock* dumpBlock = m_startBlock->GetTrueTarget(); dumpBlock != m_finalBlock;
-             dumpBlock             = dumpBlock->GetUniqueSucc())
+        dumpBlock = m_startBlock->KindIs(BBJ_COND) ? m_startBlock->GetTrueTarget() : m_startBlock->GetTarget();
+        for (; dumpBlock != m_finalBlock; dumpBlock = dumpBlock->GetUniqueSucc())
         {
             m_comp->fgDumpBlock(dumpBlock);
         }