Sort .text section to reduce fill

Author: tannewt

ports/atmel-samd/boards/common.template.ld

@@ -27,8 +27,12 @@ SECTIONS
         . = ALIGN(4);
         _sfixed = .;
         KEEP(*(.vectors)) /* isr vector table */
-        *(.text)           /* .text sections (code) */
-        *(.text*)          /* .text* sections (code) */
+
+        /* Sort text sections so that they have fewer *fill* bytes needed. */
+        *SORT_BY_ALIGNMENT(SORT_BY_NAME(.text))           /* .text sections (code) */
+        *SORT_BY_ALIGNMENT(SORT_BY_NAME(.text*))          /* .text* sections (code) */
+
+        /* Don't sort rodata because it impacts codegen size. */
         *(.rodata)         /* .rodata sections (constants, strings, etc.) */
         *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
 
@@ -62,8 +66,8 @@ SECTIONS
         _srelocate = .;        /* create a global symbol at data start; used by startup code in order to initialize the .data section in RAM */
         *(.ramfunc)
         *(.ramfunc*)
-        *(.data)           /* .data sections */
-        *(.data*)          /* .data* sections */
+        *SORT_BY_ALIGNMENT(SORT_BY_NAME(.data))           /* .data sections */
+        *SORT_BY_ALIGNMENT(SORT_BY_NAME(.data*))          /* .data* sections */
 
         . = ALIGN(4);
         _erelocate = .;        /* define a global symbol at data end; used by startup code in order to initialize the .data section in RAM */
@@ -76,7 +80,7 @@ SECTIONS
         _sbss = .;
         _szero = .;         /* define a global symbol at bss start; used by startup code */
         *(.bss)
-        *(.bss*)
+        *SORT_BY_ALIGNMENT(SORT_BY_NAME(.bss*))
         *(COMMON)
 
         . = ALIGN(4);