[Support] Recognise the '+' char for positive integers

Fixes #45326

Signed-off-by: Ebuka Ezike <[email protected]>

Author: da-viper

llvm/lib/Support/StringRef.cpp

@@ -409,6 +409,9 @@ static unsigned GetAutoSenseRadix(StringRef &Str) {
 
 bool llvm::consumeUnsignedInteger(StringRef &Str, unsigned Radix,
                                   unsigned long long &Result) {
+  // Consume the + value
+  Str.consume_front("+");
+
   // Autosense radix if not specified.
   if (Radix == 0)
     Radix = GetAutoSenseRadix(Str);

llvm/unittests/ADT/StringRefTest.cpp

@@ -622,19 +622,21 @@ TEST(StringRefTest, Hashing) {
 struct UnsignedPair {
   const char *Str;
   uint64_t Expected;
-} Unsigned[] =
-  { {"0", 0}
-  , {"255", 255}
-  , {"256", 256}
-  , {"65535", 65535}
-  , {"65536", 65536}
-  , {"4294967295", 4294967295ULL}
-  , {"4294967296", 4294967296ULL}
-  , {"18446744073709551615", 18446744073709551615ULL}
-  , {"042", 34}
-  , {"0x42", 66}
-  , {"0b101010", 42}
-  };
+} Unsigned[] = {{"0", 0},
+                {"255", 255},
+                {"256", 256},
+                {"65535", 65535},
+                {"65536", 65536},
+                {"4294967295", 4294967295ULL},
+                {"4294967296", 4294967296ULL},
+                {"18446744073709551615", 18446744073709551615ULL},
+                {"042", 34},
+                {"0x42", 66},
+                {"0b101010", 42},
+                {"+42", 42},
+                {"+042", 34},
+                {"+0x42", 66},
+                {"+0b101010", 42}};
 
 struct SignedPair {
   const char *Str;