diff --git a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
index bec23a20ac49a..167705235d516 100644
--- a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -34,6 +34,7 @@ STATISTIC(NumReadNone, "Number of functions inferred as readnone");
 STATISTIC(NumInaccessibleMemOnly,
           "Number of functions inferred as inaccessiblememonly");
 STATISTIC(NumReadOnly, "Number of functions inferred as readonly");
+STATISTIC(NumWriteOnly, "Number of functions inferred as writeonly");
 STATISTIC(NumArgMemOnly, "Number of functions inferred as argmemonly");
 STATISTIC(NumInaccessibleMemOrArgMemOnly,
           "Number of functions inferred as inaccessiblemem_or_argmemonly");
@@ -71,6 +72,14 @@ static bool setOnlyReadsMemory(Function &F) {
   return true;
 }
 
+static bool setDoesNotReadMemory(Function &F) {
+  if (F.doesNotReadMemory()) // writeonly or readnone
+    return false;
+  F.setDoesNotReadMemory();
+  ++NumWriteOnly;
+  return true;
+}
+
 static bool setOnlyAccessesArgMemory(Function &F) {
   if (F.onlyAccessesArgMemory())
     return false;
@@ -1171,6 +1180,7 @@ bool llvm::inferLibFuncAttributes(Function &F, const TargetLibraryInfo &TLI) {
   case LibFunc_truncl:
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotFreeMemory(F);
+    Changed |= setDoesNotReadMemory(F);
     Changed |= setWillReturn(F);
     return Changed;
   default:
diff --git a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
index 4fdf32b60923c..8869477231d51 100644
--- a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
+++ b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
@@ -195,76 +195,76 @@ declare double @__sinpi(double)
 ; CHECK: declare float @__sinpif(float)
 declare float @__sinpif(float)
 
-; CHECK: declare i32 @abs(i32) [[NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
+; CHECK: declare i32 @abs(i32) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY:#[0-9]+]]
 declare i32 @abs(i32)
 
 ; CHECK: declare noundef i32 @access(i8* nocapture noundef readonly, i32 noundef) [[NOFREE_NOUNWIND:#[0-9]+]]
 declare i32 @access(i8*, i32)
 
-; CHECK: declare double @acos(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @acos(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @acos(double)
 
-; CHECK: declare float @acosf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @acosf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @acosf(float)
 
-; CHECK: declare double @acosh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @acosh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @acosh(double)
 
-; CHECK: declare float @acoshf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @acoshf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @acoshf(float)
 
-; CHECK: declare x86_fp80 @acoshl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @acoshl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @acoshl(x86_fp80)
 
-; CHECK: declare x86_fp80 @acosl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @acosl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @acosl(x86_fp80)
 
 ; CHECK: declare noalias noundef i8* @aligned_alloc(i64 noundef, i64 noundef) [[INACCESSIBLEMEMONLY_NOFREE_NOUNWIND:#[0-9]+]]
 declare i8* @aligned_alloc(i64, i64)
 
-; CHECK: declare double @asin(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @asin(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @asin(double)
 
-; CHECK: declare float @asinf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @asinf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @asinf(float)
 
-; CHECK: declare double @asinh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @asinh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @asinh(double)
 
-; CHECK: declare float @asinhf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @asinhf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @asinhf(float)
 
-; CHECK: declare x86_fp80 @asinhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @asinhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @asinhl(x86_fp80)
 
-; CHECK: declare x86_fp80 @asinl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @asinl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @asinl(x86_fp80)
 
-; CHECK: declare double @atan(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @atan(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @atan(double)
 
-; CHECK: declare double @atan2(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @atan2(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @atan2(double, double)
 
-; CHECK: declare float @atan2f(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @atan2f(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @atan2f(float, float)
 
-; CHECK: declare x86_fp80 @atan2l(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @atan2l(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @atan2l(x86_fp80, x86_fp80)
 
-; CHECK: declare float @atanf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @atanf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @atanf(float)
 
-; CHECK: declare double @atanh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @atanh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @atanh(double)
 
-; CHECK: declare float @atanhf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @atanhf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @atanhf(float)
 
-; CHECK: declare x86_fp80 @atanhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @atanhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @atanhl(x86_fp80)
 
-; CHECK: declare x86_fp80 @atanl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @atanl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @atanl(x86_fp80)
 
 ; CHECK: declare double @atof(i8* nocapture) [[NOFREE_NOUNWIND_READONLY_WILLRETURN:#[0-9]+]]
@@ -289,25 +289,25 @@ declare void @bcopy(i8*, i8*, i64)
 ; CHECK: declare void @bzero(i8* nocapture writeonly, i64)  [[ARGMEMONLY_NOFREE_NOUNWIND_WILLRETURN]]
 declare void @bzero(i8*, i64)
 
-; CHECK: declare noalias noundef i8* @calloc(i64 noundef, i64 noundef) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare noalias noundef i8* @calloc(i64 noundef, i64 noundef) [[NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
 declare i8* @calloc(i64, i64)
 
-; CHECK: declare double @cbrt(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @cbrt(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @cbrt(double)
 
-; CHECK: declare float @cbrtf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @cbrtf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @cbrtf(float)
 
-; CHECK: declare x86_fp80 @cbrtl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @cbrtl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @cbrtl(x86_fp80)
 
-; CHECK: declare double @ceil(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @ceil(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @ceil(double)
 
-; CHECK: declare float @ceilf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @ceilf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @ceilf(float)
 
-; CHECK: declare x86_fp80 @ceill(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @ceill(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @ceill(x86_fp80)
 
 ; CHECK: declare noundef i32 @chmod(i8* nocapture noundef readonly, i16 noundef zeroext) [[NOFREE_NOUNWIND]]
@@ -322,70 +322,70 @@ declare void @clearerr(%opaque*)
 ; CHECK: declare noundef i32 @closedir(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare i32 @closedir(%opaque*)
 
-; CHECK: declare double @copysign(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @copysign(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @copysign(double, double)
 
-; CHECK: declare float @copysignf(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @copysignf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @copysignf(float, float)
 
-; CHECK: declare x86_fp80 @copysignl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @copysignl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @copysignl(x86_fp80, x86_fp80)
 
-; CHECK: declare double @cos(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @cos(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @cos(double)
 
-; CHECK: declare float @cosf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @cosf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @cosf(float)
 
-; CHECK: declare double @cosh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @cosh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @cosh(double)
 
-; CHECK: declare float @coshf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @coshf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @coshf(float)
 
-; CHECK: declare x86_fp80 @coshl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @coshl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @coshl(x86_fp80)
 
-; CHECK: declare x86_fp80 @cosl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @cosl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @cosl(x86_fp80)
 
 ; CHECK: declare noundef i8* @ctermid(i8* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare i8* @ctermid(i8*)
 
-; CHECK: declare double @exp(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @exp(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @exp(double)
 
-; CHECK: declare double @exp2(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @exp2(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @exp2(double)
 
-; CHECK: declare float @exp2f(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @exp2f(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @exp2f(float)
 
-; CHECK: declare x86_fp80 @exp2l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @exp2l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @exp2l(x86_fp80)
 
-; CHECK: declare float @expf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @expf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @expf(float)
 
-; CHECK: declare x86_fp80 @expl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @expl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @expl(x86_fp80)
 
-; CHECK: declare double @expm1(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @expm1(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @expm1(double)
 
-; CHECK: declare float @expm1f(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @expm1f(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @expm1f(float)
 
-; CHECK: declare x86_fp80 @expm1l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @expm1l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @expm1l(x86_fp80)
 
-; CHECK: declare double @fabs(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @fabs(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @fabs(double)
 
-; CHECK: declare float @fabsf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @fabsf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @fabsf(float)
 
-; CHECK: declare x86_fp80 @fabsl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @fabsl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @fabsl(x86_fp80)
 
 ; CHECK: declare noundef i32 @fclose(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
@@ -403,14 +403,14 @@ declare i32 @ferror(%opaque*)
 ; CHECK: declare noundef i32 @fflush(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare i32 @fflush(%opaque*)
 
-; CHECK: declare i32 @ffs(i32) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i32 @ffs(i32) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i32 @ffs(i32)
 
-; CHECK-KNOWN: declare i32 @ffsl(i64) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK-KNOWN: declare i32 @ffsl(i64) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 ; CHECK-UNKNOWN: declare i32 @ffsl(i64){{$}}
 declare i32 @ffsl(i64)
 
-; CHECK-KNOWN: declare i32 @ffsll(i64) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK-KNOWN: declare i32 @ffsll(i64) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 ; CHECK-UNKNOWN: declare i32 @ffsll(i64){{$}}
 declare i32 @ffsll(i64)
 
@@ -429,13 +429,13 @@ declare i32 @fileno(%opaque*)
 ; CHECK: declare void @flockfile(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare void @flockfile(%opaque*)
 
-; CHECK: declare double @floor(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @floor(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @floor(double)
 
-; CHECK: declare float @floorf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @floorf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @floorf(float)
 
-; CHECK: declare x86_fp80 @floorl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @floorl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @floorl(x86_fp80)
 
 ; CHECK: declare i32 @fls(i32)
@@ -447,31 +447,31 @@ declare i32 @flsl(i64)
 ; CHECK: declare i32 @flsll(i64)
 declare i32 @flsll(i64)
 
-; CHECK: declare double @fmax(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @fmax(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @fmax(double, double)
 
-; CHECK: declare float @fmaxf(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @fmaxf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @fmaxf(float, float)
 
-; CHECK: declare x86_fp80 @fmaxl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @fmaxl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @fmaxl(x86_fp80, x86_fp80)
 
-; CHECK: declare double @fmin(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @fmin(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @fmin(double, double)
 
-; CHECK: declare float @fminf(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @fminf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @fminf(float, float)
 
-; CHECK: declare x86_fp80 @fminl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @fminl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @fminl(x86_fp80, x86_fp80)
 
-; CHECK: declare double @fmod(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @fmod(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @fmod(double, double)
 
-; CHECK: declare float @fmodf(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @fmodf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @fmodf(float, float)
 
-; CHECK: declare x86_fp80 @fmodl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @fmodl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @fmodl(x86_fp80, x86_fp80)
 
 ; CHECK: declare noalias noundef %opaque* @fopen(i8* nocapture noundef readonly, i8* nocapture noundef readonly) [[NOFREE_NOUNWIND]]
@@ -578,13 +578,13 @@ declare i8* @gets(i8*)
 ; CHECK: declare noundef i32 @gettimeofday(%opaque* nocapture noundef, i8* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare i32 @gettimeofday(%opaque*, i8*)
 
-; CHECK: declare i32 @isascii(i32) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i32 @isascii(i32) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i32 @isascii(i32)
 
-; CHECK: declare i32 @isdigit(i32) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i32 @isdigit(i32) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i32 @isdigit(i32)
 
-; CHECK: declare i64 @labs(i64) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i64 @labs(i64) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i64 @labs(i64)
 
 ; CHECK: declare noundef i32 @lchown(i8* nocapture noundef readonly, i32 noundef, i32 noundef) [[NOFREE_NOUNWIND]]
@@ -599,52 +599,52 @@ declare float @ldexpf(float, i32)
 ; CHECK: declare x86_fp80 @ldexpl(x86_fp80, i32 signext) [[NOFREE_WILLRETURN]]
 declare x86_fp80 @ldexpl(x86_fp80, i32)
 
-; CHECK: declare i64 @llabs(i64) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i64 @llabs(i64) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i64 @llabs(i64)
 
-; CHECK: declare double @log(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @log(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @log(double)
 
-; CHECK: declare double @log10(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @log10(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @log10(double)
 
-; CHECK: declare float @log10f(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @log10f(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @log10f(float)
 
-; CHECK: declare x86_fp80 @log10l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @log10l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @log10l(x86_fp80)
 
-; CHECK: declare double @log1p(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @log1p(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @log1p(double)
 
-; CHECK: declare float @log1pf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @log1pf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @log1pf(float)
 
-; CHECK: declare x86_fp80 @log1pl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @log1pl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @log1pl(x86_fp80)
 
-; CHECK: declare double @log2(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @log2(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @log2(double)
 
-; CHECK: declare float @log2f(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @log2f(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @log2f(float)
 
-; CHECK: declare x86_fp80 @log2l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @log2l(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @log2l(x86_fp80)
 
-; CHECK: declare double @logb(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @logb(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @logb(double)
 
-; CHECK: declare float @logbf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @logbf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @logbf(float)
 
-; CHECK: declare x86_fp80 @logbl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @logbl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @logbl(x86_fp80)
 
-; CHECK: declare float @logf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @logf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @logf(float)
 
-; CHECK: declare x86_fp80 @logl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @logl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @logl(x86_fp80)
 
 ; CHECK: declare noundef i32 @lstat(i8* nocapture noundef readonly, %opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
@@ -703,13 +703,13 @@ declare float @modff(float, float*)
 ; CHECK: declare x86_fp80 @modfl(x86_fp80, x86_fp80* nocapture) [[NOFREE_NOUNWIND_WILLRETURN]]
 declare x86_fp80 @modfl(x86_fp80, x86_fp80*)
 
-; CHECK: declare double @nearbyint(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @nearbyint(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @nearbyint(double)
 
-; CHECK: declare float @nearbyintf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @nearbyintf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @nearbyintf(float)
 
-; CHECK: declare x86_fp80 @nearbyintl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @nearbyintl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @nearbyintl(x86_fp80)
 
 ; CHECK-LINUX: declare noundef i32 @open(i8* nocapture noundef readonly, i32 noundef, ...) [[NOFREE]]
@@ -734,13 +734,13 @@ declare %opaque* @popen(i8*, i8*)
 ; CHECK: declare i32 @posix_memalign(i8**, i64, i64) [[NOFREE]]
 declare i32 @posix_memalign(i8**, i64, i64)
 
-; CHECK: declare double @pow(double, double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @pow(double, double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @pow(double, double)
 
-; CHECK: declare float @powf(float, float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @powf(float, float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @powf(float, float)
 
-; CHECK: declare x86_fp80 @powl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @powl(x86_fp80, x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @powl(x86_fp80, x86_fp80)
 
 ; CHECK: declare noundef i64 @pread(i32 noundef, i8* nocapture noundef, i64 noundef, i64 noundef) [[NOFREE]]
@@ -792,25 +792,25 @@ declare i32 @rename(i8*, i8*)
 ; CHECK: declare void @rewind(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare void @rewind(%opaque*)
 
-; CHECK: declare double @rint(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @rint(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @rint(double)
 
-; CHECK: declare float @rintf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @rintf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @rintf(float)
 
-; CHECK: declare x86_fp80 @rintl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @rintl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @rintl(x86_fp80)
 
 ; CHECK: declare noundef i32 @rmdir(i8* nocapture noundef readonly) [[NOFREE_NOUNWIND]]
 declare i32 @rmdir(i8*)
 
-; CHECK: declare double @round(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @round(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @round(double)
 
-; CHECK: declare float @roundf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @roundf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @roundf(float)
 
-; CHECK: declare x86_fp80 @roundl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @roundl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @roundl(x86_fp80)
 
 ; CHECK: declare noundef i32 @scanf(i8* nocapture noundef readonly, ...) [[NOFREE_NOUNWIND]]
@@ -825,22 +825,22 @@ declare i32 @setitimer(i32, %opaque*, %opaque*)
 ; CHECK: declare noundef i32 @setvbuf(%opaque* nocapture noundef, i8* noundef, i32 noundef, i64 noundef) [[NOFREE_NOUNWIND]]
 declare i32 @setvbuf(%opaque*, i8*, i32, i64)
 
-; CHECK: declare double @sin(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @sin(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @sin(double)
 
-; CHECK: declare float @sinf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @sinf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @sinf(float)
 
-; CHECK: declare double @sinh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @sinh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @sinh(double)
 
-; CHECK: declare float @sinhf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @sinhf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @sinhf(float)
 
-; CHECK: declare x86_fp80 @sinhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @sinhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @sinhl(x86_fp80)
 
-; CHECK: declare x86_fp80 @sinl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @sinl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @sinl(x86_fp80)
 
 ; CHECK: declare noundef i32 @snprintf(i8* noalias nocapture noundef writeonly, i64 noundef, i8* nocapture noundef readonly, ...) [[NOFREE_NOUNWIND]]
@@ -849,13 +849,13 @@ declare i32 @snprintf(i8*, i64, i8*, ...)
 ; CHECK: declare noundef i32 @sprintf(i8* noalias nocapture noundef writeonly, i8* nocapture noundef readonly, ...) [[NOFREE_NOUNWIND]]
 declare i32 @sprintf(i8*, i8*, ...)
 
-; CHECK: declare double @sqrt(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @sqrt(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @sqrt(double)
 
-; CHECK: declare float @sqrtf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @sqrtf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @sqrtf(float)
 
-; CHECK: declare x86_fp80 @sqrtl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @sqrtl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @sqrtl(x86_fp80)
 
 ; CHECK: declare noundef i32 @sscanf(i8* nocapture noundef readonly, i8* nocapture noundef readonly, ...) [[NOFREE_NOUNWIND]]
@@ -969,22 +969,22 @@ declare i64 @strxfrm(i8*, i8*, i64)
 ; CHECK: declare noundef i32 @system(i8* nocapture noundef readonly) [[NOFREE]]
 declare i32 @system(i8*)
 
-; CHECK: declare double @tan(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @tan(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @tan(double)
 
-; CHECK: declare float @tanf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @tanf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @tanf(float)
 
-; CHECK: declare double @tanh(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @tanh(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @tanh(double)
 
-; CHECK: declare float @tanhf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @tanhf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @tanhf(float)
 
-; CHECK: declare x86_fp80 @tanhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @tanhl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @tanhl(x86_fp80)
 
-; CHECK: declare x86_fp80 @tanl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @tanl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @tanl(x86_fp80)
 
 ; CHECK: declare noundef i64 @times(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
@@ -996,16 +996,16 @@ declare %opaque* @tmpfile()
 ; CHECK-LINUX: declare noalias noundef %opaque* @tmpfile64() [[NOFREE_NOUNWIND]]
 declare %opaque* @tmpfile64()
 
-; CHECK: declare i32 @toascii(i32) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare i32 @toascii(i32) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare i32 @toascii(i32)
 
-; CHECK: declare double @trunc(double) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare double @trunc(double) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare double @trunc(double)
 
-; CHECK: declare float @truncf(float) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare float @truncf(float) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare float @truncf(float)
 
-; CHECK: declare x86_fp80 @truncl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN]]
+; CHECK: declare x86_fp80 @truncl(x86_fp80) [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]]
 declare x86_fp80 @truncl(x86_fp80)
 
 ; CHECK: declare noundef i32 @uname(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
@@ -1064,6 +1064,7 @@ declare void @memset_pattern16(i8*, i8*, i64)
 
 
 ; CHECK-DAG: attributes [[NOFREE_NOUNWIND_WILLRETURN]] = { mustprogress nofree nounwind willreturn }
+; CHECK-DAG: attributes [[NOFREE_NOUNWIND_WILLRETURN_WRITEONLY]] = { mustprogress nofree nounwind willreturn writeonly }
 ; CHECK-DAG: attributes [[NOFREE_NOUNWIND]] = { nofree nounwind }
 ; CHECK-DAG: attributes [[INACCESSIBLEMEMONLY_NOFREE_NOUNWIND_WILLRETURN]] = { inaccessiblememonly mustprogress nofree nounwind willreturn }
 ; CHECK-DAG: attributes [[NOFREE_NOUNWIND_READONLY_WILLRETURN]] = { mustprogress nofree nounwind readonly willreturn }