From: Meador Inge <meadori@codesourcery.com>
Date: Wed, 31 Oct 2012 04:29:58 +0000 (+0000)
Subject: instcombine: Migrate strpbrk optimizations
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=08684d1f069711692502d091669a6031c31cdd4a;p=oota-llvm.git

instcombine: Migrate strpbrk optimizations

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167105 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index a0235c15b61..7002eb41197 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -118,44 +118,6 @@ static bool IsOnlyUsedInEqualityComparison(Value *V, Value *With) {
 //===----------------------------------------------------------------------===//
 
 namespace {
-//===---------------------------------------===//
-// 'strpbrk' Optimizations
-
-struct StrPBrkOpt : public LibCallOptimization {
-  virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
-    FunctionType *FT = Callee->getFunctionType();
-    if (FT->getNumParams() != 2 ||
-        FT->getParamType(0) != B.getInt8PtrTy() ||
-        FT->getParamType(1) != FT->getParamType(0) ||
-        FT->getReturnType() != FT->getParamType(0))
-      return 0;
-
-    StringRef S1, S2;
-    bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
-    bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
-
-    // strpbrk(s, "") -> NULL
-    // strpbrk("", s) -> NULL
-    if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
-      return Constant::getNullValue(CI->getType());
-
-    // Constant folding.
-    if (HasS1 && HasS2) {
-      size_t I = S1.find_first_of(S2);
-      if (I == std::string::npos) // No match.
-        return Constant::getNullValue(CI->getType());
-
-      return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
-    }
-
-    // strpbrk(s, "a") -> strchr(s, 'a')
-    if (TD && HasS2 && S2.size() == 1)
-      return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
-
-    return 0;
-  }
-};
-
 //===---------------------------------------===//
 // 'strto*' Optimizations.  This handles strtol, strtod, strtof, strtoul, etc.
 
@@ -1104,7 +1066,6 @@ namespace {
 
     StringMap<LibCallOptimization*> Optimizations;
     // String and Memory LibCall Optimizations
-    StrPBrkOpt StrPBrk;
     StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
     MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
     // Math Library Optimizations
@@ -1173,7 +1134,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
 /// we know.
 void SimplifyLibCalls::InitOptimizations() {
   // String and Memory LibCall Optimizations
-  Optimizations["strpbrk"] = &StrPBrk;
   Optimizations["strtol"] = &StrTo;
   Optimizations["strtod"] = &StrTo;
   Optimizations["strtof"] = &StrTo;
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 658e7c34287..1aac8c5745d 100644
--- a/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -717,6 +717,41 @@ struct StrLenOpt : public LibCallOptimization {
   }
 };
 
+struct StrPBrkOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        FT->getParamType(1) != FT->getParamType(0) ||
+        FT->getReturnType() != FT->getParamType(0))
+      return 0;
+
+    StringRef S1, S2;
+    bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
+    bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+
+    // strpbrk(s, "") -> NULL
+    // strpbrk("", s) -> NULL
+    if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+      return Constant::getNullValue(CI->getType());
+
+    // Constant folding.
+    if (HasS1 && HasS2) {
+      size_t I = S1.find_first_of(S2);
+      if (I == std::string::npos) // No match.
+        return Constant::getNullValue(CI->getType());
+
+      return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
+    }
+
+    // strpbrk(s, "a") -> strchr(s, 'a')
+    if (TD && HasS2 && S2.size() == 1)
+      return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
+
+    return 0;
+  }
+};
+
 } // End anonymous namespace.
 
 namespace llvm {
@@ -745,6 +780,7 @@ class LibCallSimplifierImpl {
   StpCpyOpt StpCpy;
   StrNCpyOpt StrNCpy;
   StrLenOpt StrLen;
+  StrPBrkOpt StrPBrk;
 
   void initOptimizations();
 public:
@@ -777,6 +813,7 @@ void LibCallSimplifierImpl::initOptimizations() {
   Optimizations["stpcpy"] = &StpCpy;
   Optimizations["strncpy"] = &StrNCpy;
   Optimizations["strlen"] = &StrLen;
+  Optimizations["strpbrk"] = &StrPBrk;
 }
 
 Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
diff --git a/test/Transforms/InstCombine/strpbrk-1.ll b/test/Transforms/InstCombine/strpbrk-1.ll
new file mode 100644
index 00000000000..a5d0d86501b
--- /dev/null
+++ b/test/Transforms/InstCombine/strpbrk-1.ll
@@ -0,0 +1,68 @@
+; Test that the strpbrk library call simplifier works correctly.
+;
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+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 = constant [12 x i8] c"hello world\00"
+@w = constant [2 x i8] c"w\00"
+@null = constant [1 x i8] zeroinitializer
+
+declare i8* @strpbrk(i8*, i8*)
+
+; Check strpbrk(s, "") -> NULL.
+
+define i8* @test_simplify1(i8* %str) {
+; CHECK: @test_simplify1
+  %pat = getelementptr [1 x i8]* @null, i32 0, i32 0
+
+  %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+  ret i8* %ret
+; CHECK-NEXT: ret i8* null
+}
+
+; Check strpbrk("", s) -> NULL.
+
+define i8* @test_simplify2(i8* %pat) {
+; CHECK: @test_simplify2
+  %str = getelementptr [1 x i8]* @null, i32 0, i32 0
+
+  %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+  ret i8* %ret
+; CHECK-NEXT: ret i8* null
+}
+
+; Check strpbrk(s1, s2), where s1 and s2 are constants.
+
+define i8* @test_simplify3() {
+; CHECK: @test_simplify3
+  %str = getelementptr [12 x i8]* @hello, i32 0, i32 0
+  %pat = getelementptr [2 x i8]* @w, i32 0, i32 0
+
+  %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+  ret i8* %ret
+; CHECK-NEXT: ret i8* getelementptr inbounds ([12 x i8]* @hello, i32 0, i32 6)
+}
+
+; Check strpbrk(s, "a") -> strchr(s, 'a').
+
+define i8* @test_simplify4(i8* %str) {
+; CHECK: @test_simplify4
+  %pat = getelementptr [2 x i8]* @w, i32 0, i32 0
+
+  %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+; CHECK-NEXT: [[VAR:%[a-z]+]] = call i8* @strchr(i8* %str, i32 119)
+  ret i8* %ret
+; CHECK-NEXT: ret i8* [[VAR]]
+}
+
+; Check cases that shouldn't be simplified.
+
+define i8* @test_no_simplify1(i8* %str, i8* %pat) {
+; CHECK: @test_no_simplify1
+
+  %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+; CHECK-NEXT: %ret = call i8* @strpbrk(i8* %str, i8* %pat)
+  ret i8* %ret
+; CHECK-NEXT: ret i8* %ret
+}
diff --git a/test/Transforms/InstCombine/strpbrk-2.ll b/test/Transforms/InstCombine/strpbrk-2.ll
new file mode 100644
index 00000000000..31ac2905df2
--- /dev/null
+++ b/test/Transforms/InstCombine/strpbrk-2.ll
@@ -0,0 +1,23 @@
+; Test that the strpbrk library call simplifier works correctly.
+;
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+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 = constant [12 x i8] c"hello world\00"
+@w = constant [2 x i8] c"w\00"
+
+declare i16* @strpbrk(i8*, i8*)
+
+; Check that 'strpbrk' functions with the wrong prototype aren't simplified.
+
+define i16* @test_no_simplify1() {
+; CHECK: @test_no_simplify1
+  %str = getelementptr [12 x i8]* @hello, i32 0, i32 0
+  %pat = getelementptr [2 x i8]* @w, i32 0, i32 0
+
+  %ret = call i16* @strpbrk(i8* %str, i8* %pat)
+; CHECK-NEXT: %ret = call i16* @strpbrk
+  ret i16* %ret
+; CHECK-NEXT: ret i16* %ret
+}
diff --git a/test/Transforms/SimplifyLibCalls/StrPBrk.ll b/test/Transforms/SimplifyLibCalls/StrPBrk.ll
deleted file mode 100644
index 29c3b7477b4..00000000000
--- a/test/Transforms/SimplifyLibCalls/StrPBrk.ll
+++ /dev/null
@@ -1,25 +0,0 @@
-; RUN: opt < %s -simplify-libcalls -S | FileCheck %s
-
-target datalayout = "-p:64:64:64"
-
-@hello = constant [12 x i8] c"hello world\00"
-@w = constant [2 x i8] c"w\00"
-@null = constant [1 x i8] zeroinitializer
-
-declare i8* @strpbrk(i8*, i8*)
-
-define void @test(i8* %s1, i8* %s2) {
-	%hello_p = getelementptr [12 x i8]* @hello, i32 0, i32 0
-	%w_p = getelementptr [2 x i8]* @w, i32 0, i32 0
-	%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0
-	%test1 = call i8* @strpbrk(i8* %null_p, i8* %s2)
-	%test2 = call i8* @strpbrk(i8* %s1, i8* %null_p)
-; CHECK-NOT: call i8* @strpbrk
-	%test3 = call i8* @strpbrk(i8* %s1, i8* %w_p)
-; CHECK: call i8* @strchr(i8* %s1, i32 119)
-	%test4 = call i8* @strpbrk(i8* %hello_p, i8* %w_p)
-; CHECK: getelementptr i8* %hello_p, i64 6
-	%test5 = call i8* @strpbrk(i8* %s1, i8* %s2)
-; CHECK: call i8* @strpbrk(i8* %s1, i8* %s2)
-	ret void
-}