runtime: namespace LLVMSupport fork

This adds the `__swift::__runtime` inline namespace to the LLVMSupport
interfaces.  This avoids an ODR violation when LLVM and Swift are in the
same address space.  It also will aid in the process of pruning the
LLVMSupport library by ensuring that accidental leakage of the llvm
namespace does not allow us to remove symbols which we rely on.

Author: compnerd

stdlib/include/llvm/ADT/APFloat.h

@@ -31,6 +31,7 @@
     llvm_unreachable("Unexpected semantics");                                  \
   } while (false)
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 struct fltSemantics;
@@ -1321,6 +1322,7 @@ inline APFloat maximum(const APFloat &A, const APFloat &B) {
 }
 
 } // namespace llvm
+}} // swift::runtime
 
 #undef APFLOAT_DISPATCH_ON_SEMANTICS
 #endif // LLVM_ADT_APFLOAT_H

stdlib/include/llvm/ADT/APInt.h

@@ -22,6 +22,7 @@
 #include <cstring>
 #include <string>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 class FoldingSetNodeID;
 class StringRef;
@@ -2286,5 +2287,6 @@ void StoreIntToMemory(const APInt &IntVal, uint8_t *Dst, unsigned StoreBytes);
 void LoadIntFromMemory(APInt &IntVal, uint8_t *Src, unsigned LoadBytes);
 
 } // namespace llvm
+}} // namespace swift::runtime
 
 #endif

stdlib/include/llvm/ADT/APSInt.h

@@ -16,6 +16,7 @@
 
 #include "llvm/ADT/APInt.h"
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 class LLVM_NODISCARD APSInt : public APInt {
@@ -349,5 +350,6 @@ inline raw_ostream &operator<<(raw_ostream &OS, const APSInt &I) {
 }
 
 } // end namespace llvm
+}} // namespace swift::runtime
 
 #endif

stdlib/include/llvm/ADT/ArrayRef.h

@@ -24,6 +24,7 @@
 #include <type_traits>
 #include <vector>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
   /// ArrayRef - Represent a constant reference to an array (0 or more elements
@@ -554,5 +555,6 @@ namespace llvm {
   }
 
 } // end namespace llvm
+}} // namespace swift::runtime
 
 #endif // LLVM_ADT_ARRAYREF_H

stdlib/include/llvm/ADT/BitVector.h

@@ -25,6 +25,7 @@
 #include <cstring>
 #include <utility>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 /// ForwardIterator for the bits that are set.
@@ -955,6 +956,7 @@ template <> struct DenseMapInfo<BitVector> {
   }
 };
 } // end namespace llvm
+}} // namespace swift::runtime
 
 namespace std {
   /// Implement std::swap in terms of BitVector swap.

stdlib/include/llvm/ADT/DenseMap.h

@@ -31,6 +31,7 @@
 #include <type_traits>
 #include <utility>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 namespace detail {
@@ -1304,5 +1305,6 @@ inline size_t capacity_in_bytes(const DenseMap<KeyT, ValueT, KeyInfoT> &X) {
 }
 
 } // end namespace llvm
+}} // namespace swift::runtime
 
 #endif // LLVM_ADT_DENSEMAP_H

stdlib/include/llvm/ADT/DenseMapInfo.h

@@ -21,6 +21,7 @@
 #include <cstdint>
 #include <utility>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 namespace detail {
@@ -348,5 +349,6 @@ template <> struct DenseMapInfo<hash_code> {
 };
 
 } // end namespace llvm
+}} // namespace swift::runtime
 
 #endif // LLVM_ADT_DENSEMAPINFO_H

stdlib/include/llvm/ADT/DenseSet.h

@@ -23,6 +23,7 @@
 #include <iterator>
 #include <utility>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 namespace detail {
@@ -285,5 +286,6 @@ class SmallDenseSet
 };
 
 } // end namespace llvm
+}} // namespace swift::runtime
 
 #endif // LLVM_ADT_DENSESET_H

stdlib/include/llvm/ADT/EpochTracker.h

@@ -19,6 +19,7 @@
 
 #include <cstdint>
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
@@ -94,5 +95,6 @@ class DebugEpochBase {
 #endif // LLVM_ENABLE_ABI_BREAKING_CHECKS
 
 } // namespace llvm
+}} // namespace swift::runtime
 
 #endif

stdlib/include/llvm/ADT/FloatingPointMode.h

@@ -16,6 +16,7 @@
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/Support/raw_ostream.h"
 
+inline namespace __swift { inline namespace __runtime {
 namespace llvm {
 
 /// Rounding mode.
@@ -173,5 +174,6 @@ void DenormalMode::print(raw_ostream &OS) const {
 }
 
 }
+}} // namespace swift::runtime
 
 #endif // LLVM_FLOATINGPOINTMODE_H