Fix cumulative operations when axis=None (#2653)

mlx/backend/metal/device.cpp

@@ -471,6 +471,10 @@ void Device::end_encoding(int index) {
 CommandEncoder& Device::get_command_encoder(int index) {
   auto& stream = get_stream_(index);
   if (stream.encoder == nullptr) {
+    // Ensure there is an active command buffer
+    if (stream.buffer == nullptr) {
+      get_command_buffer(index);
+    }
     stream.encoder = std::make_unique<CommandEncoder>(stream);
     stream.fence = std::make_shared<Fence>(device_->newFence());
   }

mlx/ops.cpp

@@ -3468,6 +3468,14 @@ array cumsum(
       {a});
 }
 
+array cumsum(
+    const array& a,
+    bool reverse /* = false*/,
+    bool inclusive /* = true*/,
+    StreamOrDevice s /* = {}*/) {
+  return cumsum(flatten(a, to_stream(s)), 0, reverse, inclusive, to_stream(s));
+}
+
 array cumprod(
     const array& a,
     int axis,
@@ -3490,6 +3498,14 @@ array cumprod(
       {a});
 }
 
+array cumprod(
+    const array& a,
+    bool reverse /* = false*/,
+    bool inclusive /* = true*/,
+    StreamOrDevice s /* = {}*/) {
+  return cumprod(flatten(a, s), 0, reverse, inclusive, s);
+}
+
 array cummax(
     const array& a,
     int axis,
@@ -3512,6 +3528,14 @@ array cummax(
       {a});
 }
 
+array cummax(
+    const array& a,
+    bool reverse /* = false*/,
+    bool inclusive /* = true*/,
+    StreamOrDevice s /* = {}*/) {
+  return cummax(flatten(a, s), 0, reverse, inclusive, s);
+}
+
 array cummin(
     const array& a,
     int axis,
@@ -3534,6 +3558,14 @@ array cummin(
       {a});
 }
 
+array cummin(
+    const array& a,
+    bool reverse /* = false*/,
+    bool inclusive /* = true*/,
+    StreamOrDevice s /* = {}*/) {
+  return cummin(flatten(a, s), 0, reverse, inclusive, s);
+}
+
 array logcumsumexp(
     const array& a,
     int axis,
@@ -3556,6 +3588,15 @@ array logcumsumexp(
       {a});
 }
 
+array logcumsumexp(
+    const array& a,
+    bool reverse /* = false*/,
+    bool inclusive /* = true*/,
+    StreamOrDevice s /* = {}*/) {
+  return logcumsumexp(
+      flatten(a, to_stream(s)), 0, reverse, inclusive, to_stream(s));
+}
+
 /** Convolution operations */
 
 namespace {

mlx/ops.h

@@ -716,6 +716,13 @@ array topk(const array& a, int k, StreamOrDevice s = {});
 array topk(const array& a, int k, int axis, StreamOrDevice s = {});
 
 /** Cumulative logsumexp of an array. */
+array logcumsumexp(
+    const array& a,
+    bool reverse = false,
+    bool inclusive = true,
+    StreamOrDevice s = {});
+
+/** Cumulative logsumexp of an array along the given axis. */
 array logcumsumexp(
     const array& a,
     int axis,
@@ -1186,6 +1193,13 @@ softmax(const array& a, int axis, bool precise = false, StreamOrDevice s = {}) {
 array power(const array& a, const array& b, StreamOrDevice s = {});
 
 /** Cumulative sum of an array. */
+array cumsum(
+    const array& a,
+    bool reverse = false,
+    bool inclusive = true,
+    StreamOrDevice s = {});
+
+/** Cumulative sum of an array along the given axis. */
 array cumsum(
     const array& a,
     int axis,
@@ -1194,6 +1208,13 @@ array cumsum(
     StreamOrDevice s = {});
 
 /** Cumulative product of an array. */
+array cumprod(
+    const array& a,
+    bool reverse = false,
+    bool inclusive = true,
+    StreamOrDevice s = {});
+
+/** Cumulative product of an array along the given axis. */
 array cumprod(
     const array& a,
     int axis,
@@ -1202,6 +1223,13 @@ array cumprod(
     StreamOrDevice s = {});
 
 /** Cumulative max of an array. */
+array cummax(
+    const array& a,
+    bool reverse = false,
+    bool inclusive = true,
+    StreamOrDevice s = {});
+
+/** Cumulative max of an array along the given axis. */
 array cummax(
     const array& a,
     int axis,
@@ -1210,6 +1238,13 @@ array cummax(
     StreamOrDevice s = {});
 
 /** Cumulative min of an array. */
+array cummin(
+    const array& a,
+    bool reverse = false,
+    bool inclusive = true,
+    StreamOrDevice s = {});
+
+/** Cumulative min of an array along the given axis. */
 array cummin(
     const array& a,
     int axis,

python/src/array.cpp

@@ -1275,10 +1275,7 @@ void init_array(nb::module_& m) {
             if (axis) {
               return mx::logcumsumexp(a, *axis, reverse, inclusive, s);
             } else {
-              // TODO: Implement that in the C++ API as well. See concatenate
-              // above.
-              return mx::logcumsumexp(
-                  mx::reshape(a, {-1}, s), 0, reverse, inclusive, s);
+              return mx::logcumsumexp(a, reverse, inclusive, s);
             }
           },
           "axis"_a = nb::none(),
@@ -1408,9 +1405,7 @@ void init_array(nb::module_& m) {
             if (axis) {
               return mx::cumsum(a, *axis, reverse, inclusive, s);
             } else {
-              // TODO: Implement that in the C++ API as well. See concatenate
-              // above.
-              return mx::cumsum(reshape(a, {-1}, s), 0, reverse, inclusive, s);
+              return mx::cumsum(a, reverse, inclusive, s);
             }
           },
           "axis"_a = nb::none(),
@@ -1429,10 +1424,7 @@ void init_array(nb::module_& m) {
             if (axis) {
               return mx::cumprod(a, *axis, reverse, inclusive, s);
             } else {
-              // TODO: Implement that in the C++ API as well. See concatenate
-              // above.
-              return mx::cumprod(
-                  mx::reshape(a, {-1}, s), 0, reverse, inclusive, s);
+              return mx::cumprod(a, reverse, inclusive, s);
             }
           },
           "axis"_a = nb::none(),
@@ -1451,10 +1443,7 @@ void init_array(nb::module_& m) {
             if (axis) {
               return mx::cummax(a, *axis, reverse, inclusive, s);
             } else {
-              // TODO: Implement that in the C++ API as well. See concatenate
-              // above.
-              return mx::cummax(
-                  mx::reshape(a, {-1}, s), 0, reverse, inclusive, s);
+              return mx::cummax(a, reverse, inclusive, s);
             }
           },
           "axis"_a = nb::none(),
@@ -1473,10 +1462,7 @@ void init_array(nb::module_& m) {
             if (axis) {
               return mx::cummin(a, *axis, reverse, inclusive, s);
             } else {
-              // TODO: Implement that in the C++ API as well. See concatenate
-              // above.
-              return mx::cummin(
-                  mx::reshape(a, {-1}, s), 0, reverse, inclusive, s);
+              return mx::cummin(a, reverse, inclusive, s);
             }
           },
           "axis"_a = nb::none(),