update

Author: c8ef

llvm/lib/Analysis/ConstantFolding.cpp

@@ -2421,10 +2421,9 @@ static Constant *ConstantFoldScalarCall1(StringRef Name,
     case LibFunc_tgamma:
     case LibFunc_tgammaf:
       // NOTE: These boundaries are somewhat conservative.
-      if (TLI->has(Func) && (Ty->isDoubleTy() && (APF > APFloat(1 / DBL_MAX) &&
-                                                  APF < APFloat(171.0)) ||
-                             Ty->isFloatTy() && (APF > APFloat(1 / FLT_MAX) &&
-                                                 APF < APFloat(35.0f))))
+      if (TLI->has(Func) &&
+          (Ty->isDoubleTy() && APF > APFloat(DBL_MIN) && APF < APFloat(171.0) ||
+           Ty->isFloatTy() && APF > APFloat(FLT_MIN) && APF < APFloat(35.0f)))
         return ConstantFoldFP(tgamma, APF, Ty);
       break;
     case LibFunc_nearbyint:

llvm/test/Transforms/InstCombine/tgamma.ll

@@ -1,33 +1,51 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
 ; RUN: opt < %s -passes=instcombine -S | FileCheck %s
 
-define float @tgammaf_const() {
-; CHECK-LABEL: define float @tgammaf_const() {
+define float @tgammaf_in_range() {
+; CHECK-LABEL: define float @tgammaf_in_range() {
 ; CHECK-NEXT:    ret float 0x479A216280000000
 ;
   %r = call float @tgammaf(float 34.0)
   ret float %r
 }
 
-define double @tgamma_const() {
-; CHECK-LABEL: define double @tgamma_const() {
+define double @tgamma_in_range() {
+; CHECK-LABEL: define double @tgamma_in_range() {
 ; CHECK-NEXT:    ret double 0x605166C698CF183B
 ;
   %r = call double @tgamma(double 100.0)
   ret double %r
 }
 
-define float @tgammaf_const_overflow() {
-; CHECK-LABEL: define float @tgammaf_const_overflow() {
+define float @tgammaf_const_left_range() {
+; CHECK-LABEL: define float @tgammaf_const_left_range() {
+; CHECK-NEXT:    [[R:%.*]] = call float @tgammaf(float 0x3810000000000000)
+; CHECK-NEXT:    ret float [[R]]
+;
+  %r = call float @tgammaf(float 0x3810000000000000)
+  ret float %r
+}
+
+define double @tgamma_const_left_range() {
+; CHECK-LABEL: define double @tgamma_const_left_range() {
+; CHECK-NEXT:    [[R:%.*]] = call double @tgamma(double 0x10000000000000)
+; CHECK-NEXT:    ret double [[R]]
+;
+  %r = call double @tgamma(double 0x0010000000000000)
+  ret double %r
+}
+
+define float @tgammaf_const_right_range() {
+; CHECK-LABEL: define float @tgammaf_const_right_range() {
 ; CHECK-NEXT:    [[R:%.*]] = call float @tgammaf(float 3.600000e+01)
 ; CHECK-NEXT:    ret float [[R]]
 ;
   %r = call float @tgammaf(float 36.0)
   ret float %r
 }
 
-define double @tgamma_const_overflow() {
-; CHECK-LABEL: define double @tgamma_const_overflow() {
+define double @tgamma_const_right_range() {
+; CHECK-LABEL: define double @tgamma_const_right_range() {
 ; CHECK-NEXT:    [[R:%.*]] = call double @tgamma(double 1.720000e+02)
 ; CHECK-NEXT:    ret double [[R]]
 ;