[TLI] Add support for nan libfunc (#101356)

Reference: https://en.cppreference.com/w/cpp/numeric/math/nan

Author: dtcxzyw

llvm/include/llvm/Analysis/TargetLibraryInfo.def

@@ -1807,6 +1807,21 @@ TLI_DEFINE_ENUM_INTERNAL(modfl)
 TLI_DEFINE_STRING_INTERNAL("modfl")
 TLI_DEFINE_SIG_INTERNAL(LDbl, LDbl, Ptr)
 
+/// double nan(const char *arg);
+TLI_DEFINE_ENUM_INTERNAL(nan)
+TLI_DEFINE_STRING_INTERNAL("nan")
+TLI_DEFINE_SIG_INTERNAL(Dbl, Ptr)
+
+/// float nanf(const char *arg);
+TLI_DEFINE_ENUM_INTERNAL(nanf)
+TLI_DEFINE_STRING_INTERNAL("nanf")
+TLI_DEFINE_SIG_INTERNAL(Flt, Ptr)
+
+/// long double nanl(const char *arg);
+TLI_DEFINE_ENUM_INTERNAL(nanl)
+TLI_DEFINE_STRING_INTERNAL("nanl")
+TLI_DEFINE_SIG_INTERNAL(LDbl, Ptr)
+
 /// double nearbyint(double x);
 TLI_DEFINE_ENUM_INTERNAL(nearbyint)
 TLI_DEFINE_STRING_INTERNAL("nearbyint")

llvm/lib/Transforms/Utils/BuildLibCalls.cpp

@@ -279,6 +279,9 @@ bool llvm::inferNonMandatoryLibFuncAttrs(Function &F,
     Changed |= setNonLazyBind(F);
 
   switch (TheLibFunc) {
+  case LibFunc_nan:
+  case LibFunc_nanf:
+  case LibFunc_nanl:
   case LibFunc_strlen:
   case LibFunc_strnlen:
   case LibFunc_wcslen:

llvm/test/Transforms/InferFunctionAttrs/annotate.ll

@@ -717,6 +717,15 @@ declare float @modff(float, ptr)
 ; CHECK: declare x86_fp80 @modfl(x86_fp80, ptr nocapture) [[ARGMEMONLY_NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @modfl(x86_fp80, ptr)
 
+; CHECK: declare double @nan(ptr nocapture) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN:#[0-9]+]]
+declare double @nan(ptr)
+
+; CHECK: declare float @nanf(ptr nocapture) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]]
+declare float @nanf(ptr)
+
+; CHECK: declare x86_fp80 @nanl(ptr nocapture) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]]
+declare x86_fp80 @nanl(ptr)
+
 ; CHECK: declare double @nearbyint(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @nearbyint(double)
 
@@ -956,7 +965,7 @@ declare ptr @strncpy(ptr, ptr, i64)
 ; CHECK: declare noalias ptr @strndup(ptr nocapture readonly, i64 noundef) [[INACCESSIBLEMEMORARGONLY_NOFREE_NOUNWIND_WILLRETURN_FAMILY_MALLOC]]
 declare ptr @strndup(ptr, i64)
 
-; CHECK: declare i64 @strnlen(ptr nocapture, i64) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN:#[0-9]+]]
+; CHECK: declare i64 @strnlen(ptr nocapture, i64) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]]
 declare i64 @strnlen(ptr, i64)
 
 ; CHECK: declare ptr @strpbrk(ptr, ptr nocapture) [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]]

llvm/test/tools/llvm-tli-checker/ps4-tli-check.yaml

@@ -34,21 +34,21 @@
 #
 # CHECK: << Total TLI yes SDK no:  8
 # CHECK: >> Total TLI no  SDK yes: 0
-# CHECK: == Total TLI yes SDK yes: 245
+# CHECK: == Total TLI yes SDK yes: 248
 #
 # WRONG_DETAIL: << TLI yes SDK no : '_ZdaPv' aka operator delete[](void*)
 # WRONG_DETAIL: >> TLI no  SDK yes: '_ZdaPvj' aka operator delete[](void*, unsigned int)
 # WRONG_DETAIL-COUNT-8: << TLI yes SDK no : {{.*}}__hot_cold_t
 # WRONG_SUMMARY: << Total TLI yes SDK no:  9{{$}}
 # WRONG_SUMMARY: >> Total TLI no  SDK yes: 1{{$}}
-# WRONG_SUMMARY: == Total TLI yes SDK yes: 244
+# WRONG_SUMMARY: == Total TLI yes SDK yes: 247
 #
 ## The -COUNT suffix doesn't care if there are too many matches, so check
 ## the exact count first; the two directives should add up to that.
 ## Yes, this means additions to TLI will fail this test, but the argument
 ## to -COUNT can't be an expression.
-# AVAIL: TLI knows 486 symbols, 253 available
-# AVAIL-COUNT-253: {{^}} available
+# AVAIL: TLI knows 489 symbols, 256 available
+# AVAIL-COUNT-256: {{^}} available
 # AVAIL-NOT:       {{^}} available
 # UNAVAIL-COUNT-233: not available
 # UNAVAIL-NOT:       not available
@@ -703,6 +703,18 @@ DynamicSymbols:
     Type:            STT_FUNC
     Section:         .text
     Binding:         STB_GLOBAL
+  - Name:            nan
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
+  - Name:            nanf
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
+  - Name:            nanl
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
   - Name:            nearbyint
     Type:            STT_FUNC
     Section:         .text

llvm/unittests/Analysis/TargetLibraryInfoTest.cpp

@@ -255,6 +255,9 @@ TEST_F(TargetLibraryInfoTest, ValidProto) {
       "declare double @modf(double, double*)\n"
       "declare float @modff(float, float*)\n"
       "declare x86_fp80 @modfl(x86_fp80, x86_fp80*)\n"
+      "declare double @nan(ptr)\n"
+      "declare float @nanf(ptr)\n"
+      "declare x86_fp80 @nanl(ptr)\n"
       "declare double @nearbyint(double)\n"
       "declare float @nearbyintf(float)\n"
       "declare x86_fp80 @nearbyintl(x86_fp80)\n"