Add the Pure attribute to C99 builtin functions from ctype.h. This is a...

Add the Pure attribute to C99 builtin functions from ctype.h. This is a corrected version of r266199 with test case fixes.

Patch by Taewook Oh.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268553 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/Builtins.def

@@ -67,6 +67,7 @@
 // Builtin::Context class.  Currently we have:
 //  n -> nothrow
 //  r -> noreturn
+//  U -> pure
 //  c -> const
 //  t -> signature is meaningless, use custom typechecking
 //  F -> this is a libc/libm function with a '__builtin_' prefix added.
@@ -773,6 +774,22 @@ LIBBUILTIN(sscanf, "icC*RcC*R.",  "fs:1:", "stdio.h", ALL_LANGUAGES)
 LIBBUILTIN(vscanf, "icC*Ra",      "fS:0:", "stdio.h", ALL_LANGUAGES)
 LIBBUILTIN(vfscanf, "iP*RcC*Ra",  "fS:1:", "stdio.h", ALL_LANGUAGES)
 LIBBUILTIN(vsscanf, "icC*RcC*Ra", "fS:1:", "stdio.h", ALL_LANGUAGES)
+// C99 ctype.h
+LIBBUILTIN(isalnum, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isalpha, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isblank, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(iscntrl, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isdigit, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isgraph, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(islower, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isprint, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(ispunct, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isspace, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isupper, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(isxdigit, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(tolower, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+LIBBUILTIN(toupper, "ii", "fnU", "ctype.h", ALL_LANGUAGES)
+
 // C99
 // In some systems setjmp is a macro that expands to _setjmp. We undefine
 // it here to avoid having two identical LIBBUILTIN entries.

include/clang/Basic/Builtins.h

@@ -89,11 +89,16 @@ public:
     return getRecord(ID).Type;
   }
 
-  /// \brief Return true if this function is a target-specific builtin
+  /// \brief Return true if this function is a target-specific builtin.
   bool isTSBuiltin(unsigned ID) const {
     return ID >= Builtin::FirstTSBuiltin;
   }
 
+  /// \brief Return true if this function has no side effects.
+  bool isPure(unsigned ID) const {
+    return strchr(getRecord(ID).Attributes, 'U') != nullptr;
+  }
+
   /// \brief Return true if this function has no side effects and doesn't
   /// read memory.
   bool isConst(unsigned ID) const {
@@ -155,7 +160,7 @@ public:
   /// \brief Completely forget that the given ID was ever considered a builtin,
   /// e.g., because the user provided a conflicting signature.
   void forgetBuiltin(unsigned ID, IdentifierTable &Table);
-  
+
   /// \brief If this is a library function that comes from a specific
   /// header, retrieve that header name.
   const char *getHeaderName(unsigned ID) const {

test/FixIt/typo.m

@@ -113,8 +113,6 @@ void test2(Collide *a) {
   
 @end
 
-double *isupper(int);
-
 @interface Sub2 : Super
 - (int)method2;
 @end

test/Sema/enable_if.c

@@ -72,8 +72,8 @@ int isdigit(int c) __attribute__((overloadable))  // expected-note{{candidate fu
   __attribute__((unavailable("'c' must have the value of an unsigned char or EOF")));
 
 void test3(int c) {
-  isdigit(c);
-  isdigit(10);
+  isdigit(c); // expected-warning{{ignoring return value of function declared with pure attribute}}
+  isdigit(10); // expected-warning{{ignoring return value of function declared with pure attribute}}
 #ifndef CODEGEN
   isdigit(-10);  // expected-error{{call to unavailable function 'isdigit': 'c' must have the value of an unsigned char or EOF}}
 #endif

test/Sema/libbuiltins-ctype-powerpc64.c

+// RUN: %clang_cc1 -triple powerpc64-unknown-linux-gnu -emit-llvm < %s | FileCheck %s
+
+int isalnum(int);
+int isalpha(int);
+int isblank(int);
+int iscntrl(int);
+int isdigit(int);
+int isgraph(int);
+int islower(int);
+int isprint(int);
+int ispunct(int);
+int isspace(int);
+int isupper(int);
+int isxdigit(int);
+int tolower(int);
+int toupper(int);
+
+void test(int x) {
+  // CHECK: call signext i32 @isalnum(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isalnum(x);
+  // CHECK: call signext i32 @isalpha(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isalpha(x);
+  // CHECK: call signext i32 @isblank(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isblank(x);
+  // CHECK: call signext i32 @iscntrl(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)iscntrl(x);
+  // CHECK: call signext i32 @isdigit(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isdigit(x);
+  // CHECK: call signext i32 @isgraph(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isgraph(x);
+  // CHECK: call signext i32 @islower(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)islower(x);
+  // CHECK: call signext i32 @isprint(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isprint(x);
+  // CHECK: call signext i32 @ispunct(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)ispunct(x);
+  // CHECK: call signext i32 @isspace(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isspace(x);
+  // CHECK: call signext i32 @isupper(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isupper(x);
+  // CHECK: call signext i32 @isxdigit(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isxdigit(x);
+  // CHECK: call signext i32 @tolower(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)tolower(x);
+  // CHECK: call signext i32 @toupper(i32 signext {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)toupper(x);
+}
+
+// CHECK: declare signext i32 @isalnum(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isalpha(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isblank(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @iscntrl(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isdigit(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isgraph(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @islower(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isprint(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @ispunct(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isspace(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isupper(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @isxdigit(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @tolower(i32 signext) [[NUW_RO:#[0-9]+]]
+// CHECK: declare signext i32 @toupper(i32 signext) [[NUW_RO:#[0-9]+]]
+
+// CHECK: attributes [[NUW_RO]] = { nounwind readonly{{.*}} }
+// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly }

test/Sema/libbuiltins-ctype-x86_64.c

+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm < %s | FileCheck %s
+
+int isalnum(int);
+int isalpha(int);
+int isblank(int);
+int iscntrl(int);
+int isdigit(int);
+int isgraph(int);
+int islower(int);
+int isprint(int);
+int ispunct(int);
+int isspace(int);
+int isupper(int);
+int isxdigit(int);
+int tolower(int);
+int toupper(int);
+
+void test(int x) {
+  // CHECK: call i32 @isalnum(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isalnum(x);
+  // CHECK: call i32 @isalpha(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isalpha(x);
+  // CHECK: call i32 @isblank(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isblank(x);
+  // CHECK: call i32 @iscntrl(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)iscntrl(x);
+  // CHECK: call i32 @isdigit(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isdigit(x);
+  // CHECK: call i32 @isgraph(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isgraph(x);
+  // CHECK: call i32 @islower(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)islower(x);
+  // CHECK: call i32 @isprint(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isprint(x);
+  // CHECK: call i32 @ispunct(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)ispunct(x);
+  // CHECK: call i32 @isspace(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isspace(x);
+  // CHECK: call i32 @isupper(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isupper(x);
+  // CHECK: call i32 @isxdigit(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)isxdigit(x);
+  // CHECK: call i32 @tolower(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)tolower(x);
+  // CHECK: call i32 @toupper(i32 {{%[0-9]+}}) [[NUW_RO_CALL:#[0-9]+]]
+  (void)toupper(x);
+}
+
+// CHECK: declare i32 @isalnum(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isalpha(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isblank(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @iscntrl(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isdigit(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isgraph(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @islower(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isprint(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @ispunct(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isspace(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isupper(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @isxdigit(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @tolower(i32) [[NUW_RO:#[0-9]+]]
+// CHECK: declare i32 @toupper(i32) [[NUW_RO:#[0-9]+]]
+
+// CHECK: attributes [[NUW_RO]] = { nounwind readonly{{.*}} }
+// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly }