From: Richard Osborne <richard@xmos.com>
Date: Thu, 3 Mar 2011 14:09:28 +0000 (+0000)
Subject: Optimize sprintf -> siprintf if there are no floating point arguments
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=419454ad3720b8cf4613d9e790669c8beaccd1a4;p=oota-llvm.git

Optimize sprintf -> siprintf if there are no floating point arguments
and siprintf is available on the target.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126937 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/Target/TargetLibraryInfo.h b/include/llvm/Target/TargetLibraryInfo.h
index bc119e11cb7..8474fc57bc6 100644
--- a/include/llvm/Target/TargetLibraryInfo.h
+++ b/include/llvm/Target/TargetLibraryInfo.h
@@ -29,6 +29,9 @@ namespace llvm {
       /// int iprintf(const char *format, ...);
       iprintf,
       
+      /// int siprintf(char *str, const char *format, ...);
+      siprintf,
+      
       NumLibFuncs
     };
   }
diff --git a/lib/Target/TargetLibraryInfo.cpp b/lib/Target/TargetLibraryInfo.cpp
index 6bf6c0d1a6b..345d914a580 100644
--- a/lib/Target/TargetLibraryInfo.cpp
+++ b/lib/Target/TargetLibraryInfo.cpp
@@ -31,9 +31,11 @@ static void initialize(TargetLibraryInfo &TLI, const Triple &T) {
   if (T.getOS() != Triple::Darwin || T.getDarwinMajorNumber() < 9)
     TLI.setUnavailable(LibFunc::memset_pattern16);
 
-  // iprintf is only available on XCore.
-  if (T.getArch() != Triple::xcore)
+  // iprintf and friends are only available on XCore.
+  if (T.getArch() != Triple::xcore) {
     TLI.setUnavailable(LibFunc::iprintf);
+    TLI.setUnavailable(LibFunc::siprintf);
+  }
 }
 
 
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index c0bef26291a..60f235ce3c8 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -1176,14 +1176,8 @@ struct PrintFOpt : public LibCallOptimization {
 // 'sprintf' Optimizations
 
 struct SPrintFOpt : public LibCallOptimization {
-  virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
-    // Require two fixed pointer arguments and an integer result.
-    const FunctionType *FT = Callee->getFunctionType();
-    if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
-        !FT->getParamType(1)->isPointerTy() ||
-        !FT->getReturnType()->isIntegerTy())
-      return 0;
-
+  Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
+                                   IRBuilder<> &B) {
     // Check for a fixed format string.
     std::string FormatStr;
     if (!GetConstantStringInfo(CI->getArgOperand(1), FormatStr))
@@ -1244,6 +1238,32 @@ struct SPrintFOpt : public LibCallOptimization {
     }
     return 0;
   }
+
+  virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Require two fixed pointer arguments and an integer result.
+    const FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        !FT->getReturnType()->isIntegerTy())
+      return 0;
+
+    if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
+      return V;
+    }
+
+    // sprintf(str, format, ...) -> iprintf(str, format, ...) if no floating
+    // point arguments.
+    if (TLI->has(LibFunc::siprintf) && !CallHasFloatingPointArgument(CI)) {
+      Module *M = B.GetInsertBlock()->getParent()->getParent();
+      Constant *SIPrintFFn =
+        M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
+      CallInst *New = cast<CallInst>(CI->clone());
+      New->setCalledFunction(SIPrintFFn);
+      B.Insert(New);
+      return New;
+    }
+    return 0;
+  }
 };
 
 //===---------------------------------------===//
diff --git a/test/Transforms/SimplifyLibCalls/iprintf.ll b/test/Transforms/SimplifyLibCalls/iprintf.ll
index 11385cb75d4..b99de6efb87 100644
--- a/test/Transforms/SimplifyLibCalls/iprintf.ll
+++ b/test/Transforms/SimplifyLibCalls/iprintf.ll
@@ -26,4 +26,25 @@ entry:
 	ret void
 }
 
+; Verify sprintf with no floating point arguments is transformed to siprintf
+define i32 @f2(i8* %p, i32 %x) nounwind {
+entry:
+; CHECK: define i32 @f2
+; CHECK: @siprintf
+; CHECK: }
+	%0 = tail call i32 (i8*, i8*, ...)* @sprintf(i8 *%p, i8* getelementptr ([4 x i8]* @.str1, i32 0, i32 0), i32 %x)
+	ret i32 %0
+}
+
+; Verify we don't turn this into an siprintf call
+define i32 @f3(i8* %p, double %x) nounwind {
+entry:
+; CHECK: define i32 @f3
+; CHECK: @sprintf
+; CHECK: }
+	%0 = tail call i32 (i8*, i8*, ...)* @sprintf(i8 *%p, i8* getelementptr ([4 x i8]* @.str, i32 0, i32 0), double %x)
+	ret i32 %0
+}
+
 declare i32 @printf(i8* nocapture, ...) nounwind
+declare i32 @sprintf(i8* nocapture, i8* nocapture, ...) nounwind