[WebAssembly] Add Emscripten OS definition + small_printf

The Emscripten OS provides a definition of __EMSCRIPTEN__, and also that it
supports iprintf optimizations.

Also define small_printf optimizations, which is a printf with float support
but not long double (which in wasm can be useful since long doubles are 128
bit and force linking of float128 emulation code). This part is based on
sunfish's https://reviews.llvm.org/D57620 (which can't land yet since
the WASI integration isn't ready yet).

Differential Revision: https://reviews.llvm.org/D60167

llvm-svn: 357552

1 files changed, 13 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() &&