3 files changed, 63 insertions, 2 deletions

diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
index 50a05a897e9..b74e1ceeb93 100644
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -165,13 +165,21 @@ static void initialize(TargetLibraryInfoImpl &TLI, const Triple &T,
     TLI.setAvailableWithName(LibFunc_fputs, "fputs$UNIX2003");
   }
 
-  // iprintf and friends are only available on XCore and TCE.
-  if (T.getArch() != Triple::xcore && T.getArch() != Triple::tce) {
+  // iprintf and friends are only available on XCore, TCE, and Emscripten.
+  if (T.getArch() != Triple::xcore && T.getArch() != Triple::tce &&
+      T.getOS() != Triple::Emscripten) {
     TLI.setUnavailable(LibFunc_iprintf);
     TLI.setUnavailable(LibFunc_siprintf);
     TLI.setUnavailable(LibFunc_fiprintf);
   }
 
+  // __small_printf and friends are only available on Emscripten.
+  if (T.getOS() != Triple::Emscripten) {
+    TLI.setUnavailable(LibFunc_small_printf);
+    TLI.setUnavailable(LibFunc_small_sprintf);
+    TLI.setUnavailable(LibFunc_small_fprintf);
+  }
+
   if (T.isOSWindows() && !T.isOSCygMing()) {
     // XXX: The earliest documentation available at the moment is for VS2015/VC19:
     // https://docs.microsoft.com/en-us/cpp/c-runtime-library/floating-point-support?view=vs-2015
@@ -771,6 +779,7 @@ bool TargetLibraryInfoImpl::isValidProtoForLibFunc(const FunctionType &FTy,
   case LibFunc_stat:
   case LibFunc_statvfs:
   case LibFunc_siprintf:
+  case LibFunc_small_sprintf:
   case LibFunc_sprintf:
     return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
             FTy.getParamType(1)->isPointerTy() &&
@@ -868,6 +877,7 @@ bool TargetLibraryInfoImpl::isValidProtoForLibFunc(const FunctionType &FTy,
   case LibFunc_getenv:
   case LibFunc_getpwnam:
   case LibFunc_iprintf:
+  case LibFunc_small_printf:
   case LibFunc_pclose:
   case LibFunc_perror:
   case LibFunc_printf:
@@ -947,6 +957,7 @@ bool TargetLibraryInfoImpl::isValidProtoForLibFunc(const FunctionType &FTy,
             FTy.getParamType(1)->isPointerTy());
   case LibFunc_fscanf:
   case LibFunc_fiprintf:
+  case LibFunc_small_fprintf:
   case LibFunc_fprintf:
     return (NumParams >= 2 && FTy.getReturnType()->isIntegerTy() &&
             FTy.getParamType(0)->isPointerTy() &&
diff --git a/llvm/lib/Support/Triple.cpp b/llvm/lib/Support/Triple.cpp
index 83ce4f0f122..a5a25d20400 100644
--- a/llvm/lib/Support/Triple.cpp
+++ b/llvm/lib/Support/Triple.cpp
@@ -208,6 +208,7 @@ StringRef Triple::getOSTypeName(OSType Kind) {
   case HermitCore: return "hermit";
   case Hurd: return "hurd";
   case WASI: return "wasi";
+  case Emscripten: return "emscripten";
   }
 
   llvm_unreachable("Invalid OSType");
@@ -506,6 +507,7 @@ static Triple::OSType parseOS(StringRef OSName) {
     .StartsWith("hermit", Triple::HermitCore)
     .StartsWith("hurd", Triple::Hurd)
     .StartsWith("wasi", Triple::WASI)
+    .StartsWith("emscripten", Triple::Emscripten)
     .Default(Triple::UnknownOS);
 }
 
diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 3920736a8d5..0af79f4b236 100644
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -104,6 +104,12 @@ static bool callHasFloatingPointArgument(const CallInst *CI) {
   });
 }
 
+static bool callHasFP128Argument(const CallInst *CI) {
+  return any_of(CI->operands(), [](const Use &OI) {
+    return OI->getType()->isFP128Ty();
+  });
+}
+
 static Value *convertStrToNumber(CallInst *CI, StringRef &Str, int64_t Base) {
   if (Base < 2 || Base > 36)
     // handle special zero base
@@ -2051,6 +2057,20 @@ Value *LibCallSimplifier::optimizePrintF(CallInst *CI, IRBuilder<> &B) {
     B.Insert(New);
     return New;
   }
+
+  // printf(format, ...) -> __small_printf(format, ...) if no 128-bit floating point
+  // arguments.
+  if (TLI->has(LibFunc_small_printf) && !callHasFP128Argument(CI)) {
+    Module *M = B.GetInsertBlock()->getParent()->getParent();
+    auto SmallPrintFFn =
+        M->getOrInsertFunction(TLI->getName(LibFunc_small_printf),
+                               FT, Callee->getAttributes());
+    CallInst *New = cast<CallInst>(CI->clone());
+    New->setCalledFunction(SmallPrintFFn);
+    B.Insert(New);
+    return New;
+  }
+
   return nullptr;
 }
 
@@ -2131,6 +2151,20 @@ Value *LibCallSimplifier::optimizeSPrintF(CallInst *CI, IRBuilder<> &B) {
     B.Insert(New);
     return New;
   }
+
+  // sprintf(str, format, ...) -> __small_sprintf(str, format, ...) if no 128-bit
+  // floating point arguments.
+  if (TLI->has(LibFunc_small_sprintf) && !callHasFP128Argument(CI)) {
+    Module *M = B.GetInsertBlock()->getParent()->getParent();
+    auto SmallSPrintFFn =
+        M->getOrInsertFunction(TLI->getName(LibFunc_small_sprintf),
+                               FT, Callee->getAttributes());
+    CallInst *New = cast<CallInst>(CI->clone());
+    New->setCalledFunction(SmallSPrintFFn);
+    B.Insert(New);
+    return New;
+  }
+
   return nullptr;
 }
 
@@ -2288,6 +2322,20 @@ Value *LibCallSimplifier::optimizeFPrintF(CallInst *CI, IRBuilder<> &B) {
     B.Insert(New);
     return New;
   }
+
+  // fprintf(stream, format, ...) -> __small_fprintf(stream, format, ...) if no
+  // 128-bit floating point arguments.
+  if (TLI->has(LibFunc_small_fprintf) && !callHasFP128Argument(CI)) {
+    Module *M = B.GetInsertBlock()->getParent()->getParent();
+    auto SmallFPrintFFn =
+        M->getOrInsertFunction(TLI->getName(LibFunc_small_fprintf),
+                               FT, Callee->getAttributes());
+    CallInst *New = cast<CallInst>(CI->clone());
+    New->setCalledFunction(SmallFPrintFFn);
+    B.Insert(New);
+    return New;
+  }
+
   return nullptr;
 }