[rom] Measure ROM space utilization

1. Add a script to transform the mapfile to json and visualize the
   space utilization with a `d3.js` treemap.
2. Add a build config to disable hardening and measure the impact
   of hardening on code size.

Signed-off-by: Chris Frantz <[email protected]>
(cherry picked from commit bc285b7)

Author: cfrantz

.bazelrc

@@ -19,6 +19,10 @@ build --strip='never'
 # impact of the hardened sequences on code size.
 build:disable_hardening --features=-guards --copt=-DOT_DISABLE_HARDENING=1
 
+# Use --config=disable_hardening to disable hardening to measure the
+# impact of the hardened sequences on code size.
+build:disable_hardening --features=-guards --copt=-DOT_DISABLE_HARDENING=1
+
 # Enable toolchain resolution with cc
 build --incompatible_enable_cc_toolchain_resolution
 

sw/device/lib/base/hardened.h

@@ -241,8 +241,7 @@ inline uint32_t launder32(uint32_t val) {
 
   // When we're building for static analysis, reduce false positives by
   // short-circuiting the inline assembly block.
-#if OT_BUILD_FOR_STATIC_ANALYZER || \
-    (defined(OT_DISABLE_HARDENING) && OT_DISABLE_HARDENING)
+#if OT_BUILD_FOR_STATIC_ANALYZER || OT_DISABLE_HARDENING
   return val;
 #endif
 
@@ -264,8 +263,7 @@ inline uint32_t launder32(uint32_t val) {
  */
 OT_WARN_UNUSED_RESULT
 inline uintptr_t launderw(uintptr_t val) {
-#if OT_BUILD_FOR_STATIC_ANALYZER || \
-    (defined(OT_DISABLE_HARDENING) && OT_DISABLE_HARDENING)
+#if OT_BUILD_FOR_STATIC_ANALYZER || OT_DISABLE_HARDENING
   return val;
 #endif
   asm volatile("" : "+r"(val));