instcombine: Migrate sprintf optimizations

This patch migrates the sprintf optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168677 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/SimplifyLibCalls.cpp

@@ -99,102 +99,6 @@ namespace {
 // Formatting and IO Optimizations
 //===----------------------------------------------------------------------===//
 
-//===---------------------------------------===//
-// 'sprintf' Optimizations
-
-struct SPrintFOpt : public LibCallOptimization {
-  Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
-                                   IRBuilder<> &B) {
-    // Check for a fixed format string.
-    StringRef FormatStr;
-    if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
-      return 0;
-
-    // If we just have a format string (nothing else crazy) transform it.
-    if (CI->getNumArgOperands() == 2) {
-      // Make sure there's no % in the constant array.  We could try to handle
-      // %% -> % in the future if we cared.
-      for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
-        if (FormatStr[i] == '%')
-          return 0; // we found a format specifier, bail out.
-
-      // These optimizations require DataLayout.
-      if (!TD) return 0;
-
-      // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
-      B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
-                     ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
-                                      FormatStr.size() + 1), 1);   // nul byte.
-      return ConstantInt::get(CI->getType(), FormatStr.size());
-    }
-
-    // The remaining optimizations require the format string to be "%s" or "%c"
-    // and have an extra operand.
-    if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
-        CI->getNumArgOperands() < 3)
-      return 0;
-
-    // Decode the second character of the format string.
-    if (FormatStr[1] == 'c') {
-      // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
-      if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
-      Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
-      Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
-      B.CreateStore(V, Ptr);
-      Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
-      B.CreateStore(B.getInt8(0), Ptr);
-
-      return ConstantInt::get(CI->getType(), 1);
-    }
-
-    if (FormatStr[1] == 's') {
-      // These optimizations require DataLayout.
-      if (!TD) return 0;
-
-      // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
-      if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
-
-      Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
-      if (!Len)
-        return 0;
-      Value *IncLen = B.CreateAdd(Len,
-                                  ConstantInt::get(Len->getType(), 1),
-                                  "leninc");
-      B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
-
-      // The sprintf result is the unincremented number of bytes in the string.
-      return B.CreateIntCast(Len, CI->getType(), false);
-    }
-    return 0;
-  }
-
-  virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
-    // Require two fixed pointer arguments and an integer result.
-    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, ...) -> siprintf(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;
-  }
-};
-
 //===---------------------------------------===//
 // 'fwrite' Optimizations
 
@@ -376,7 +280,6 @@ namespace {
 
     StringMap<LibCallOptimization*> Optimizations;
     // Formatting and IO Optimizations
-    SPrintFOpt SPrintF;
     FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
     PutsOpt Puts;
 
@@ -434,7 +337,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
 /// we know.
 void SimplifyLibCalls::InitOptimizations() {
   // Formatting and IO Optimizations
-  Optimizations["sprintf"] = &SPrintF;
   AddOpt(LibFunc::fwrite, &FWrite);
   AddOpt(LibFunc::fputs, &FPuts);
   Optimizations["fprintf"] = &FPrintF;

lib/Transforms/Utils/SimplifyLibCalls.cpp

@@ -1409,6 +1409,99 @@ struct PrintFOpt : public LibCallOptimization {
   }
 };
 
+struct SPrintFOpt : public LibCallOptimization {
+  Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
+                                   IRBuilder<> &B) {
+    // Check for a fixed format string.
+    StringRef FormatStr;
+    if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
+      return 0;
+
+    // If we just have a format string (nothing else crazy) transform it.
+    if (CI->getNumArgOperands() == 2) {
+      // Make sure there's no % in the constant array.  We could try to handle
+      // %% -> % in the future if we cared.
+      for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+        if (FormatStr[i] == '%')
+          return 0; // we found a format specifier, bail out.
+
+      // These optimizations require DataLayout.
+      if (!TD) return 0;
+
+      // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
+      B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+                     ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
+                                      FormatStr.size() + 1), 1);   // nul byte.
+      return ConstantInt::get(CI->getType(), FormatStr.size());
+    }
+
+    // The remaining optimizations require the format string to be "%s" or "%c"
+    // and have an extra operand.
+    if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
+        CI->getNumArgOperands() < 3)
+      return 0;
+
+    // Decode the second character of the format string.
+    if (FormatStr[1] == 'c') {
+      // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
+      if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
+      Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
+      Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
+      B.CreateStore(V, Ptr);
+      Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
+      B.CreateStore(B.getInt8(0), Ptr);
+
+      return ConstantInt::get(CI->getType(), 1);
+    }
+
+    if (FormatStr[1] == 's') {
+      // These optimizations require DataLayout.
+      if (!TD) return 0;
+
+      // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
+      if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
+
+      Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
+      if (!Len)
+        return 0;
+      Value *IncLen = B.CreateAdd(Len,
+                                  ConstantInt::get(Len->getType(), 1),
+                                  "leninc");
+      B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
+
+      // The sprintf result is the unincremented number of bytes in the string.
+      return B.CreateIntCast(Len, CI->getType(), false);
+    }
+    return 0;
+  }
+
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Require two fixed pointer arguments and an integer result.
+    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, ...) -> siprintf(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;
+  }
+};
+
 } // End anonymous namespace.
 
 namespace llvm {
@@ -1464,6 +1557,7 @@ class LibCallSimplifierImpl {
 
   // Formatting and IO library call optimizations.
   PrintFOpt PrintF;
+  SPrintFOpt SPrintF;
 
   void initOptimizations();
   void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1588,6 +1682,7 @@ void LibCallSimplifierImpl::initOptimizations() {
 
   // Formatting and IO library call optimizations.
   addOpt(LibFunc::printf, &PrintF);
+  addOpt(LibFunc::sprintf, &SPrintF);
 }
 
 Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {

test/Transforms/SimplifyLibCalls/2010-05-30-memcpy-Struct.ll → test/Transforms/InstCombine/2010-05-30-memcpy-Struct.ll

@@ -1,16 +1,16 @@
-; RUN: opt -simplify-libcalls %s -S -o - | FileCheck %s
+; RUN: opt -instcombine %s -S -o - | FileCheck %s
 ; PR7265
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-unknown-linux-gnu"
 
 %union.anon = type { i32, [4 x i8] }
 
-@.str = private constant [3 x i8] c"%s\00"        ; <[3 x i8]*> [#uses=2]
+@.str = private constant [3 x i8] c"%s\00"
 
 define void @CopyEventArg(%union.anon* %ev) nounwind {
 entry:
-  %call = call i32 (i8*, i8*, ...)* @sprintf(i8* undef, i8* getelementptr inbounds ([3 x i8]* @.str, i64 0, i64 0), %union.anon* %ev) nounwind ; <i32> [#uses=0]
+  %call = call i32 (i8*, i8*, ...)* @sprintf(i8* undef, i8* getelementptr inbounds ([3 x i8]* @.str, i64 0, i64 0), %union.anon* %ev) nounwind
 ; CHECK: bitcast %union.anon* %ev to i8*
 ; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64
   ret void

test/Transforms/InstCombine/sprintf-1.ll

@@ -0,0 +1,80 @@
+; Test that the sprintf library call simplifier works correctly.
+;
+; RUN: opt < %s -instcombine -S | FileCheck %s
+; RUN: opt < %s -mtriple xcore-xmos-elf -instcombine -S | FileCheck %s -check-prefix=IPRINTF
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+
+@hello_world = constant [13 x i8] c"hello world\0A\00"
+@h = constant [2 x i8] c"h\00"
+@percent_c = constant [3 x i8] c"%c\00"
+@percent_d = constant [3 x i8] c"%d\00"
+@percent_f = constant [3 x i8] c"%f\00"
+@percent_s = constant [3 x i8] c"%s\00"
+
+declare i32 @sprintf(i8*, i8*, ...)
+
+; Check sprintf(dst, fmt) -> llvm.memcpy(str, fmt, strlen(fmt) + 1, 1).
+
+define void @test_simplify1(i8* %dst) {
+; CHECK: @test_simplify1
+  %fmt = getelementptr [13 x i8]* @hello_world, i32 0, i32 0
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt)
+; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* getelementptr inbounds ([13 x i8]* @hello_world, i32 0, i32 0), i32 13, i32 1, i1 false)
+  ret void
+; CHECK-NEXT: ret void
+}
+
+; Check sprintf(dst, "%c", chr) -> *(i8*)dst = chr; *((i8*)dst + 1) = 0.
+
+define void @test_simplify2(i8* %dst) {
+; CHECK: @test_simplify2
+  %fmt = getelementptr [3 x i8]* @percent_c, i32 0, i32 0
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, i8 104)
+; CHECK-NEXT: store i8 104, i8* %dst, align 1
+; CHECK-NEXT: [[NUL:%[a-z0-9]+]] = getelementptr i8* %dst, i32 1
+; CHECK-NEXT: store i8 0, i8* [[NUL]], align 1
+  ret void
+; CHECK-NEXT: ret void
+}
+
+; Check sprintf(dst, "%s", str) -> llvm.memcpy(dest, str, strlen(str) + 1, 1).
+
+define void @test_simplify3(i8* %dst, i8* %str) {
+; CHECK: @test_simplify3
+  %fmt = getelementptr [3 x i8]* @percent_s, i32 0, i32 0
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, i8* %str)
+; CHECK-NEXT: [[STRLEN:%[a-z0-9]+]] = call i32 @strlen(i8* %str)
+; CHECK-NEXT: [[LENINC:%[a-z0-9]+]] = add i32 [[STRLEN]], 1
+; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %str, i32 [[LENINC]], i32 1, i1 false)
+  ret void
+; CHECK-NEXT: ret void
+}
+
+; Check sprintf(dst, format, ...) -> siprintf(str, format, ...) if no floating.
+
+define void @test_simplify4(i8* %dst) {
+; CHECK-IPRINTF: @test_simplify4
+  %fmt = getelementptr [3 x i8]* @percent_d, i32 0, i32 0
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, i32 187)
+; CHECK-NEXT-IPRINTF: call i32 (i8*, i8*, ...)* @siprintf(i8* %dst, i8* getelementptr inbounds ([3 x i8]* @percent_d, i32 0, i32 0), i32 187)
+  ret void
+; CHECK-NEXT-IPRINTF: ret void
+}
+
+define void @test_no_simplify1(i8* %dst) {
+; CHECK-IPRINTF: @test_no_simplify1
+  %fmt = getelementptr [3 x i8]* @percent_f, i32 0, i32 0
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, double 1.87)
+; CHECK-NEXT-IPRINTF: call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* getelementptr inbounds ([3 x i8]* @percent_f, i32 0, i32 0), double 1.870000e+00)
+  ret void
+; CHECK-NEXT-IPRINTF: ret void
+}
+
+define void @test_no_simplify2(i8* %dst, i8* %fmt, double %d) {
+; CHECK: @test_no_simplify2
+  call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, double %d)
+; CHECK-NEXT: call i32 (i8*, i8*, ...)* @sprintf(i8* %dst, i8* %fmt, double %d)
+  ret void
+; CHECK-NEXT: ret void
+}

test/Transforms/SimplifyLibCalls/iprintf.ll

@@ -6,26 +6,6 @@ target triple = "xcore-xmos-elf"
 @.str = internal constant [4 x i8] c"%f\0A\00"		; <[4 x i8]*> [#uses=1]
 @.str1 = internal constant [4 x i8] c"%d\0A\00"		; <[4 x i8]*> [#uses=1]
 
-; 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
-}
-
 ; Verify fprintf with no floating point arguments is transformed to fiprintf
 define i32 @f4(i8* %p, i32 %x) nounwind {
 entry:
@@ -46,5 +26,4 @@ entry:
 	ret i32 %0
 }
 
-declare i32 @sprintf(i8* nocapture, i8* nocapture, ...) nounwind
 declare i32 @fprintf(i8* nocapture, i8* nocapture, ...) nounwind