From eb3602472026dc029beb45ccbe09bc84162ba949 Mon Sep 17 00:00:00 2001
From: Aaron Ballman <aaron@aaronballman.com>
Date: Wed, 13 Nov 2013 00:15:44 +0000
Subject: [PATCH] Replacing HUGE_VALF with llvm::huge_valf in order to work
 around a warning triggered in MSVC 12.

Patch reviewed by Reid Kleckner and Jim Grosbach.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194533 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/LiveInterval.h  |  4 ++--
 include/llvm/Support/MathExtras.h    | 14 +++++++++++++-
 lib/CodeGen/LiveIntervalAnalysis.cpp |  3 ++-
 lib/CodeGen/RegAllocGreedy.cpp       |  6 +++---
 lib/CodeGen/Spiller.cpp              |  2 +-
 5 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h
index 1b30bf5937e..3a9fef6fbd7 100644
--- a/include/llvm/CodeGen/LiveInterval.h
+++ b/include/llvm/CodeGen/LiveInterval.h
@@ -541,12 +541,12 @@ namespace llvm {
 
     /// isSpillable - Can this interval be spilled?
     bool isSpillable() const {
-      return weight != HUGE_VALF;
+      return weight != llvm::huge_valf;
     }
 
     /// markNotSpillable - Mark interval as not spillable
     void markNotSpillable() {
-      weight = HUGE_VALF;
+      weight = llvm::huge_valf;
     }
 
     bool operator<(const LiveInterval& other) const {
diff --git a/include/llvm/Support/MathExtras.h b/include/llvm/Support/MathExtras.h
index 00c6ad70d43..17cf4751a01 100644
--- a/include/llvm/Support/MathExtras.h
+++ b/include/llvm/Support/MathExtras.h
@@ -21,7 +21,8 @@
 #include <cstring>
 
 #ifdef _MSC_VER
-# include <intrin.h>
+#include <intrin.h>
+#include <limits>
 #endif
 
 namespace llvm {
@@ -603,6 +604,17 @@ inline int64_t SignExtend64(uint64_t X, unsigned B) {
   return int64_t(X << (64 - B)) >> (64 - B);
 }
 
+#if defined(_MSC_VER)
+  // Visual Studio defines the HUGE_VAL class of macros using purposeful
+  // constant arithmetic overflow, which it then warns on when encountered.
+  const float huge_valf = std::numeric_limits<float>::infinity();
+  const double huge_vald = std::numeric_limits<double>::infinity();
+  const long double huge_vall = std::numeric_limits<long double>::infinity();
+#else
+  const float huge_valf = HUGE_VALF;
+  const double huge_vald = HUGE_VALD;
+  const long double huge_vall = HUGE_VALL;
+#endif
 } // End llvm namespace
 
 #endif
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 7a3b3051162..e1c3217a775 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -170,7 +170,8 @@ void LiveIntervals::dumpInstrs() const {
 #endif
 
 LiveInterval* LiveIntervals::createInterval(unsigned reg) {
-  float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ? HUGE_VALF : 0.0F;
+  float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ?
+                  llvm::huge_valf : 0.0F;
   return new LiveInterval(reg, Weight);
 }
 
diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp
index 95b30a4823b..c08d9555406 100644
--- a/lib/CodeGen/RegAllocGreedy.cpp
+++ b/lib/CodeGen/RegAllocGreedy.cpp
@@ -1477,7 +1477,7 @@ void RAGreedy::calcGapWeights(unsigned PhysReg,
         break;
 
       for (; Gap != NumGaps; ++Gap) {
-        GapWeight[Gap] = HUGE_VALF;
+        GapWeight[Gap] = llvm::huge_valf;
         if (Uses[Gap+1].getBaseIndex() >= I->end)
           break;
       }
@@ -1583,7 +1583,7 @@ unsigned RAGreedy::tryLocalSplit(LiveInterval &VirtReg, AllocationOrder &Order,
     // Remove any gaps with regmask clobbers.
     if (Matrix->checkRegMaskInterference(VirtReg, PhysReg))
       for (unsigned i = 0, e = RegMaskGaps.size(); i != e; ++i)
-        GapWeight[RegMaskGaps[i]] = HUGE_VALF;
+        GapWeight[RegMaskGaps[i]] = llvm::huge_valf;
 
     // Try to find the best sequence of gaps to close.
     // The new spill weight must be larger than any gap interference.
@@ -1618,7 +1618,7 @@ unsigned RAGreedy::tryLocalSplit(LiveInterval &VirtReg, AllocationOrder &Order,
       // Legally, without causing looping?
       bool Legal = !ProgressRequired || NewGaps < NumGaps;
 
-      if (Legal && MaxGap < HUGE_VALF) {
+      if (Legal && MaxGap < llvm::huge_valf) {
         // Estimate the new spill weight. Each instruction reads or writes the
         // register. Conservatively assume there are no read-modify-write
         // instructions.
diff --git a/lib/CodeGen/Spiller.cpp b/lib/CodeGen/Spiller.cpp
index d72c596a842..d5b3a4a9400 100644
--- a/lib/CodeGen/Spiller.cpp
+++ b/lib/CodeGen/Spiller.cpp
@@ -77,7 +77,7 @@ protected:
 
     DEBUG(dbgs() << "Spilling everywhere " << *li << "\n");
 
-    assert(li->weight != HUGE_VALF &&
+    assert(li->weight != llvm::huge_valf &&
            "Attempting to spill already spilled value.");
 
     assert(!TargetRegisterInfo::isStackSlot(li->reg) &&
-- 
2.34.1