auto merge of #4938 : thestinger/rust/no_zero, r=brson

I removed the unused wrappers methods named `calloc` because they relied on the malloc wrapper having a `bool zero = true` default parameter (which resulted in some accidental zeroing). Perhaps wrapping the actual calloc function would be useful, but I don't know of an existing use case that could use it so I just removed these.

This gives an ~1% performance improvement for TreeMap, which does a lot of small allocations. Vectors use `realloc` which didn't zero before these changes so there's no measurable change in performance.

8 files changed, 8 insertions, 36 deletions

diff --git a/src/rt/memory_region.cpp b/src/rt/memory_region.cpp
index 6307730b0f4..6de9d5a1df4 100644
--- a/src/rt/memory_region.cpp
+++ b/src/rt/memory_region.cpp
@@ -121,8 +121,10 @@ memory_region::realloc(void *mem, size_t orig_size) {
 }
 
 void *
-memory_region::malloc(size_t size, const char *tag, bool zero) {
+memory_region::malloc(size_t size, const char *tag) {
+#   if RUSTRT_TRACK_ALLOCATIONS >= 1
     size_t old_size = size;
+#   endif
     size += HEADER_SIZE;
     alloc_header *mem = (alloc_header *)::malloc(size);
     if (mem == NULL) {
@@ -143,18 +145,9 @@ memory_region::malloc(size_t size, const char *tag, bool zero) {
     void *data = get_data(mem);
     claim_alloc(data);
 
-    if(zero) {
-        memset(data, 0, old_size);
-    }
-
     return data;
 }
 
-void *
-memory_region::calloc(size_t size, const char *tag) {
-    return malloc(size, tag, true);
-}
-
 memory_region::~memory_region() {
     if (_synchronized) { _lock.lock(); }
     if (_live_allocations == 0 && !_detailed_leaks) {
diff --git a/src/rt/memory_region.h b/src/rt/memory_region.h
index 7a68a0f8af5..999a992eefa 100644
--- a/src/rt/memory_region.h
+++ b/src/rt/memory_region.h
@@ -77,8 +77,7 @@ private:
 public:
     memory_region(rust_env *env, bool synchronized);
     memory_region(memory_region *parent);
-    void *malloc(size_t size, const char *tag, bool zero = true);
-    void *calloc(size_t size, const char *tag);
+    void *malloc(size_t size, const char *tag);
     void *realloc(void *mem, size_t size);
     void free(void *mem);
     ~memory_region();
diff --git a/src/rt/rust_exchange_alloc.cpp b/src/rt/rust_exchange_alloc.cpp
index 6c0204ca736..a92bc4edd41 100644
--- a/src/rt/rust_exchange_alloc.cpp
+++ b/src/rt/rust_exchange_alloc.cpp
@@ -18,12 +18,9 @@
 uintptr_t exchange_count = 0;
 
 void *
-rust_exchange_alloc::malloc(size_t size, bool zero) {
+rust_exchange_alloc::malloc(size_t size) {
   void *value = ::malloc(size);
   assert(value);
-  if (zero) {
-    memset(value, 0, size);
-  }
 
   sync::increment(exchange_count);
 
@@ -31,11 +28,6 @@ rust_exchange_alloc::malloc(size_t size, bool zero) {
 }
 
 void *
-rust_exchange_alloc::calloc(size_t size) {
-  return this->malloc(size);
-}
-
-void *
 rust_exchange_alloc::realloc(void *ptr, size_t size) {
   void *new_ptr = ::realloc(ptr, size);
   assert(new_ptr);
diff --git a/src/rt/rust_exchange_alloc.h b/src/rt/rust_exchange_alloc.h
index 1b52929acf1..767caf01323 100644
--- a/src/rt/rust_exchange_alloc.h
+++ b/src/rt/rust_exchange_alloc.h
@@ -16,8 +16,7 @@
 
 class rust_exchange_alloc {
  public:
-    void *malloc(size_t size, bool zero = true);
-    void *calloc(size_t size);
+    void *malloc(size_t size);
     void *realloc(void *mem, size_t size);
     void free(void *mem);
 };
diff --git a/src/rt/rust_kernel.cpp b/src/rt/rust_kernel.cpp
index 6b7a8241416..4d2d6ad344c 100644
--- a/src/rt/rust_kernel.cpp
+++ b/src/rt/rust_kernel.cpp
@@ -80,11 +80,6 @@ rust_kernel::malloc(size_t size, const char *tag) {
 }
 
 void *
-rust_kernel::calloc(size_t size, const char *tag) {
-    return exchange_alloc.calloc(size);
-}
-
-void *
 rust_kernel::realloc(void *mem, size_t size) {
     return exchange_alloc.realloc(mem, size);
 }
diff --git a/src/rt/rust_kernel.h b/src/rt/rust_kernel.h
index 01ebf5ab57b..e65a0bd9289 100644
--- a/src/rt/rust_kernel.h
+++ b/src/rt/rust_kernel.h
@@ -133,7 +133,6 @@ public:
     void fatal(char const *fmt, ...);
 
     void *malloc(size_t size, const char *tag);
-    void *calloc(size_t size, const char *tag);
     void *realloc(void *mem, size_t size);
     void free(void *mem);
     rust_exchange_alloc *region() { return &exchange_alloc; }
diff --git a/src/rt/rust_stack.cpp b/src/rt/rust_stack.cpp
index 3bcda8adf40..64ca256ff46 100644
--- a/src/rt/rust_stack.cpp
+++ b/src/rt/rust_stack.cpp
@@ -58,7 +58,7 @@ check_stack_canary(stk_seg *stk) {
 stk_seg *
 create_stack(memory_region *region, size_t sz) {
     size_t total_sz = sizeof(stk_seg) + sz;
-    stk_seg *stk = (stk_seg *)region->malloc(total_sz, "stack", false);
+    stk_seg *stk = (stk_seg *)region->malloc(total_sz, "stack");
     memset(stk, 0, sizeof(stk_seg));
     stk->end = (uintptr_t) &stk->data[sz];
     add_stack_canary(stk);
@@ -75,7 +75,7 @@ destroy_stack(memory_region *region, stk_seg *stk) {
 stk_seg *
 create_exchange_stack(rust_exchange_alloc *exchange, size_t sz) {
     size_t total_sz = sizeof(stk_seg) + sz;
-    stk_seg *stk = (stk_seg *)exchange->malloc(total_sz, false);
+    stk_seg *stk = (stk_seg *)exchange->malloc(total_sz);
     memset(stk, 0, sizeof(stk_seg));
     stk->end = (uintptr_t) &stk->data[sz];
     add_stack_canary(stk);
diff --git a/src/rt/rust_task.cpp b/src/rt/rust_task.cpp
index e51af464e48..63dc1c9833e 100644
--- a/src/rt/rust_task.cpp
+++ b/src/rt/rust_task.cpp
@@ -450,11 +450,6 @@ rust_task::backtrace() {
 #endif
 }
 
-void *
-rust_task::calloc(size_t size, const char *tag) {
-    return local_region.calloc(size, tag);
-}
-
 size_t
 rust_task::get_next_stack_size(size_t min, size_t current, size_t requested) {
     LOG(this, mem, "calculating new stack size for 0x%" PRIxPTR, this);