Merge branch 'gandrade/fmod/PR-1216/OTP-14000'

* gandrade/fmod/PR-1216/OTP-14000:
  Add test cases for math:fmod/2 BIF
  Support math:fmod/2 BIF on compiler
  Add math:fmod/2 BIF

8 files changed, 24 insertions, 1 deletions

diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
index 852b1135fe..32600f4338 100644
--- a/erts/emulator/beam/bif.tab
+++ b/erts/emulator/beam/bif.tab
@@ -667,6 +667,7 @@ gcbif erlang:floor/1
 gcbif erlang:ceil/1
 bif math:floor/1
 bif math:ceil/1
+bif math:fmod/2
 
 #
 # Obsolete
diff --git a/erts/emulator/beam/erl_math.c b/erts/emulator/beam/erl_math.c
index 990fa63bd4..1f270eb55f 100644
--- a/erts/emulator/beam/erl_math.c
+++ b/erts/emulator/beam/erl_math.c
@@ -256,3 +256,8 @@ BIF_RETTYPE math_floor_1(BIF_ALIST_1)
 {
     return math_call_1(BIF_P, floor, BIF_ARG_1);
 }
+
+BIF_RETTYPE math_fmod_2(BIF_ALIST_2)
+{
+    return math_call_2(BIF_P, fmod, BIF_ARG_1, BIF_ARG_2);
+}
diff --git a/lib/compiler/src/beam_type.erl b/lib/compiler/src/beam_type.erl
index b4776294be..d324580cba 100644
--- a/lib/compiler/src/beam_type.erl
+++ b/lib/compiler/src/beam_type.erl
@@ -594,6 +594,7 @@ is_math_bif(atan2, 2) -> true;
 is_math_bif(pow, 2) -> true;
 is_math_bif(ceil, 1) -> true;
 is_math_bif(floor, 1) -> true;
+is_math_bif(fmod, 2) -> true;
 is_math_bif(pi, 0) -> true;
 is_math_bif(_, _) -> false.
 
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 6e53f53a20..5659077c5d 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -1646,6 +1646,7 @@ return_type_math(atan2, 2) -> {float,[]};
 return_type_math(pow, 2) -> {float,[]};
 return_type_math(ceil, 1) -> {float,[]};
 return_type_math(floor, 1) -> {float,[]};
+return_type_math(fmod, 2) -> {float,[]};
 return_type_math(pi, 0) -> {float,[]};
 return_type_math(F, A) when is_atom(F), is_integer(A), A >= 0 -> term.
 
diff --git a/lib/compiler/src/erl_bifs.erl b/lib/compiler/src/erl_bifs.erl
index 831730ba48..d60f73d421 100644
--- a/lib/compiler/src/erl_bifs.erl
+++ b/lib/compiler/src/erl_bifs.erl
@@ -138,6 +138,7 @@ is_pure(math, erf, 1) -> true;
 is_pure(math, erfc, 1) -> true;
 is_pure(math, exp, 1) -> true;
 is_pure(math, floor, 1) -> true;
+is_pure(math, fmod, 2) -> true;
 is_pure(math, log, 1) -> true;
 is_pure(math, log2, 1) -> true;
 is_pure(math, log10, 1) -> true;
diff --git a/lib/compiler/test/float_SUITE.erl b/lib/compiler/test/float_SUITE.erl
index 0ebc71eb9b..08c3dd8593 100644
--- a/lib/compiler/test/float_SUITE.erl
+++ b/lib/compiler/test/float_SUITE.erl
@@ -155,6 +155,13 @@ math_functions(Config) when is_list(Config) ->
     5.0 = math:floor(id(5.4)),
     6.0 = math:ceil(id(5.4)),
 
+    0.0 = math:fmod(42, 42),
+    0.25 = math:fmod(1, 0.75),
+    -1.0 = math:fmod(-4.0, 1.5),
+    -0.375 = math:fmod(-3.0, -0.875),
+    0.125 = math:fmod(8.125, -4),
+    {'EXIT',{badarith,_}} = (catch math:fmod(5.0, 0.0)),
+
     %% Only for coverage (of beam_type.erl).
     {'EXIT',{undef,_}} = (catch math:fnurfla(0)),
     {'EXIT',{undef,_}} = (catch math:fnurfla(0, 0)),
diff --git a/lib/stdlib/doc/src/math.xml b/lib/stdlib/doc/src/math.xml
index 70ca6ae78e..b4f096217a 100644
--- a/lib/stdlib/doc/src/math.xml
+++ b/lib/stdlib/doc/src/math.xml
@@ -62,6 +62,7 @@
       <name name="cosh" arity="1"/>
       <name name="exp" arity="1"/>
       <name name="floor" arity="1"/>
+      <name name="fmod" arity="2"/>
       <name name="log" arity="1"/>
       <name name="log10" arity="1"/>
       <name name="log2" arity="1"/>
diff --git a/lib/stdlib/src/math.erl b/lib/stdlib/src/math.erl
index 1db48cd0a2..3a3b384d8f 100644
--- a/lib/stdlib/src/math.erl
+++ b/lib/stdlib/src/math.erl
@@ -26,7 +26,8 @@
 -export([sin/1, cos/1, tan/1, asin/1, acos/1, atan/1, atan2/2, sinh/1,
          cosh/1, tanh/1, asinh/1, acosh/1, atanh/1, exp/1, log/1,
          log2/1, log10/1, pow/2, sqrt/1, erf/1, erfc/1,
-	 ceil/1, floor/1]).
+         ceil/1, floor/1,
+         fmod/2]).
 
 -spec acos(X) -> float() when
       X :: number().
@@ -99,6 +100,11 @@ exp(_) ->
 floor(_) ->
     erlang:nif_error(undef).
 
+-spec fmod(X, Y) -> float() when
+      X :: number(), Y :: number().
+fmod(_, _) ->
+    erlang:nif_error(undef).
+
 -spec log(X) -> float() when
       X :: number().
 log(_) ->