diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/exec-formats-and-tools.md | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/docs/exec-formats-and-tools.md b/docs/exec-formats-and-tools.md index 4ae43e4..fc3b995 100644 --- a/docs/exec-formats-and-tools.md +++ b/docs/exec-formats-and-tools.md @@ -9,7 +9,7 @@ architecture and the use of plain mips-elf GCC toolchain. Then the next simple template can be used to compile assembly source codes. -''' +``` #define zero $0 #define at $1 #define v0 $2 @@ -61,7 +61,7 @@ loop: break .end _start -''' +``` The simulator recognizes 'break' instruction @@ -90,10 +90,10 @@ is not a good idea to set up breakpoint to address of an instruction in the delay slot. To compile simple assembly code programs invoke GCC with next options. -''' +``` mips-elf-gcc -ggdb -c program.S -o program.o mips-elf-gcc -ggdb -nostdlib -nodefaultlibs -nostartfiles program.o -o program -''' +``` Compile Executables with 'mips-linux-gnu' Toolchain --------------------------------------------------- @@ -110,7 +110,7 @@ and 't9' register value. The startup code which conforms these requirements to call 'main()' function looks like this: -''' +``` /* file crt0local.S - replacement of C library complete startup machinery */ .globl main .globl __start @@ -141,7 +141,7 @@ loop: break nop .end __start -''' +``` The sequence of relative jump and link to next instruction setups return address register 'ra' @@ -152,7 +152,7 @@ offset into global data area from actual instruction address and stores result in the 'gp' -''' +``` 00400500 <__start>: 400500: 04110001 bal 400508 <next> 400504: 00000000 nop @@ -174,7 +174,7 @@ address and stores result in the 'gp' 400534: 0000000d break 400538: 1000fffe b 400534 <loop> 40053c: 00000000 nop -''' +``` It can be seen that assembler not only expands '.cpload' but even marks 'jalr t9' instruction as a target for @@ -187,7 +187,7 @@ Then simple main function which outputs string to the serial port provided by QtMisp emulator can be implemented as: -''' +``` /* serial-port-test.c */ #include <stdint.h> @@ -222,21 +222,21 @@ int main(void) return 0; } -''' +``` Compilation: -''' +``` mips-linux-gnu-gcc -ggdb -fno-lto -c crt0local.S -o crt0local.o mips-linux-gnu-gcc -ggdb -O3 -fno-lto -c serial-port-test.c -o serial-port-test.o mips-linux-gnu-gcc -ggdb -nostartfiles -static -fno-lto crt0local.o serial-port-test.o -o serial-port-test -''' +``` The simulator implements 'rdhwr $rd, userlocal' instrcution and allows code compiled agains musl C library to start as well. -''' +``` mips-linux-gnu-gcc -ggdb -O1 -march=mips2 -static -specs=/opt/musl/mips-linux-gnu/lib/musl-gcc.specs -c program.c -o program.o mips-linux-gnu-gcc -ggdb -march=mips2 -static -specs=/opt/musl/mips-linux-gnu/lib/musl-gcc.specs programo -o program -''' +``` |