Function Layout, Global Variable Layout and Pooled Constants Layout Reordering

src/IceTargetLoweringX8632.cpp

 //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===//
 //
 //                        The Subzero Code Generator
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the TargetLoweringX8632 class, which
 // consists almost entirely of the lowering sequence for each
 // high-level instruction.
 //
@@ skipping 221 matching lines @@
   if (!BuildDefs::dump())
     return;
   Ostream &Str = Ctx->getStrEmit();
   Type Ty = T::Ty;
   SizeT Align = typeAlignInBytes(Ty);
   ConstantList Pool = Ctx->getConstantPool(Ty);
 
   Str << "\t.section\t.rodata.cst" << Align << ",\"aM\",@progbits," << Align
       << "\n";
   Str << "\t.align\t" << Align << "\n";
+
+  // If reorder-pooled-constants option is set to true, we need to shuffle the
+  // constant pool before emitting it.
+  if (Ctx->getFlags().shouldReorderPooledConstants())
+    RandomShuffle(Pool.begin(), Pool.end(), [Ctx](uint64_t N) {
+      return (uint32_t)Ctx->getRNG().next(N);
+    });
+
   for (Constant *C : Pool) {
     if (!C->getShouldBePooled())
       continue;
     typename T::IceType *Const = llvm::cast<typename T::IceType>(C);
     typename T::IceType::PrimType Value = Const->getValue();
     // Use memcpy() to copy bits from Value into RawValue in a way
     // that avoids breaking strict-aliasing rules.
     typename T::PrimitiveIntType RawValue;
     memcpy(&RawValue, &Value, sizeof(Value));
     char buf[30];
@@ skipping 163 matching lines @@
 // entries in case the high-level table has extra entries.
 #define X(tag, size, align, elts, elty, str)                                   \
   static_assert(_table1_##tag == _table2_##tag,                                \
                 "Inconsistency between ICETYPEX8632_TABLE and ICETYPE_TABLE");
 ICETYPE_TABLE
 #undef X
 } // end of namespace dummy3
 } // end of anonymous namespace
 
 } // end of namespace Ice