Adds hello world

This commit is contained in:
Henry Case 2019-01-09 17:54:18 +00:00
parent e6a210e0c4
commit b0e6f0813d
4 changed files with 10 additions and 38 deletions

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@ -1,25 +0,0 @@
#include <stdio.h>
uint64_t getcycles();
static void do_something()
{
for (int i = 0; i < 1000; ++i) {
__asm__("NOP");
}
}
int main(void)
{
// Instruction cache misses are relatively expensive, so for more
// consistent benchmarks that depend less on the relative speed of
// the QSPI flash, you might want to fill the instruction cache first.
// Note that it can hold 16 KiB of instructions on the HiFive1.
do_something();
getcycles();
uint64_t oldcount = getcycles();
do_something();
uint64_t newcount = getcycles();
printf("That took %d cycles.\n", (unsigned int)(newcount-oldcount));
return 0;
}

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@ -1,10 +0,0 @@
.text
.globl getcycles
.align 2
getcycles:
csrr a1, mcycleh
csrr a0, mcycle
csrr a2, mcycleh
bne a1, a2, getcycles
ret

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@ -1,6 +1,6 @@
TARGET := cyclecount.elf
LOCAL_SRC_C := cyclecount.c
LOCAL_SRC_S := getcycles.S
TARGET := helloriscv.elf
LOCAL_SRC_C := helloriscv.c
LOCAL_SRC_S :=
LOCAL_OPT_C := -Os -fno-builtin-printf -Wall -Wextra -pedantic
include ../conf/toolchain.mk

7
helloworld/helloriscv.c Normal file
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@ -0,0 +1,7 @@
#include <stdio.h>
int main(void)
{
printf("Hello RISC-V");
return 0;
}