[TLI] Add basic support for fdim libcall (#108702)

first PR to fix #108695

Signed-off-by: Kushal Pal <[email protected]>

Author: braw-lee

llvm/include/llvm/Analysis/TargetLibraryInfo.def

@@ -2067,6 +2067,21 @@ TLI_DEFINE_ENUM_INTERNAL(remquol)
 TLI_DEFINE_STRING_INTERNAL("remquol")
 TLI_DEFINE_SIG_INTERNAL(LDbl, LDbl, LDbl, Ptr)
 
+/// double fdim(double x, double y);
+TLI_DEFINE_ENUM_INTERNAL(fdim)
+TLI_DEFINE_STRING_INTERNAL("fdim")
+TLI_DEFINE_SIG_INTERNAL(Dbl, Dbl, Dbl)
+
+/// float fdimf(float x, float y);
+TLI_DEFINE_ENUM_INTERNAL(fdimf)
+TLI_DEFINE_STRING_INTERNAL("fdimf")
+TLI_DEFINE_SIG_INTERNAL(Flt, Flt, Flt)
+
+/// long double fdiml(long double x, long double y);
+TLI_DEFINE_ENUM_INTERNAL(fdiml)
+TLI_DEFINE_STRING_INTERNAL("fdiml")
+TLI_DEFINE_SIG_INTERNAL(LDbl, LDbl, LDbl)
+
 /// int remove(const char *path);
 TLI_DEFINE_ENUM_INTERNAL(remove)
 TLI_DEFINE_STRING_INTERNAL("remove")

llvm/lib/Analysis/TargetLibraryInfo.cpp

@@ -306,6 +306,7 @@ static void initializeLibCalls(TargetLibraryInfoImpl &TLI, const Triple &T,
       TLI.setUnavailable(LibFunc_powf);
       TLI.setUnavailable(LibFunc_remainderf);
       TLI.setUnavailable(LibFunc_remquof);
+      TLI.setUnavailable(LibFunc_fdimf);
       TLI.setUnavailable(LibFunc_sinf);
       TLI.setUnavailable(LibFunc_sinhf);
       TLI.setUnavailable(LibFunc_sqrtf);
@@ -337,6 +338,7 @@ static void initializeLibCalls(TargetLibraryInfoImpl &TLI, const Triple &T,
     TLI.setUnavailable(LibFunc_powl);
     TLI.setUnavailable(LibFunc_remainderl);
     TLI.setUnavailable(LibFunc_remquol);
+    TLI.setUnavailable(LibFunc_fdiml);
     TLI.setUnavailable(LibFunc_sinl);
     TLI.setUnavailable(LibFunc_sinhl);
     TLI.setUnavailable(LibFunc_sqrtl);

llvm/lib/Transforms/Utils/BuildLibCalls.cpp

@@ -1191,6 +1191,9 @@ bool llvm::inferNonMandatoryLibFuncAttrs(Function &F,
   case LibFunc_fabs:
   case LibFunc_fabsf:
   case LibFunc_fabsl:
+  case LibFunc_fdim:
+  case LibFunc_fdiml:
+  case LibFunc_fdimf:
   case LibFunc_ffs:
   case LibFunc_ffsl:
   case LibFunc_ffsll:

llvm/test/Transforms/InferFunctionAttrs/annotate.ll

@@ -830,6 +830,16 @@ declare float @remquof(float, float, ptr)
 ; CHECK: declare x86_fp80 @remquol(x86_fp80, x86_fp80, ptr nocapture) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @remquol(x86_fp80, x86_fp80, ptr)
 
+
+; CHECK: declare double @fdim(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
+declare double @fdim(double, double)
+
+; CHECK: declare float @fdimf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
+declare float @fdimf(float, float)
+
+; CHECK: declare x86_fp80 @fdiml(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
+declare x86_fp80 @fdiml(x86_fp80, x86_fp80)
+
 ; CHECK: declare noundef i32 @rename(ptr nocapture noundef readonly, ptr nocapture noundef readonly) [[NOFREE_NOUNWIND]]
 declare i32 @rename(ptr, ptr)
 

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

@@ -814,6 +814,18 @@ DynamicSymbols:
     Type:            STT_FUNC
     Section:         .text
     Binding:         STB_GLOBAL
+  - Name:            fdim
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
+  - Name:            fdimf
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
+  - Name:            fdiml
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
   - Name:            rewind
     Type:            STT_FUNC
     Section:         .text

llvm/unittests/Analysis/TargetLibraryInfoTest.cpp

@@ -317,6 +317,9 @@ TEST_F(TargetLibraryInfoTest, ValidProto) {
       "declare double @remquo(double, double, ptr)\n"
       "declare float @remquof(float, float, ptr)\n"
       "declare x86_fp80 @remquol(x86_fp80, x86_fp80, ptr)\n"
+      "declare double @fdim(double, double)\n"
+      "declare float @fdimf(float, float)\n"
+      "declare x86_fp80 @fdiml(x86_fp80, x86_fp80)\n"
       "declare i32 @rename(i8*, i8*)\n"
       "declare void @rewind(%struct*)\n"
       "declare double @rint(double)\n"