[PATCH v2 nolibc 16/53] tools/nolibc: riscv: Fix up load/store instructions for rv32

Paul E. McKenney
2023-06-12T20:48:14Z

From: Zhangjin Wu <falcon@tinylab.org>

When compile nolibc application for rv32, we got such errors:
nolibc/sysroot/riscv/include/arch.h:190: Error: unrecognized opcode `ld a4,0(a3)'
nolibc/sysroot/riscv/include/arch.h:194: Error: unrecognized opcode `sd a3,%lo(_auxv)(a4)'
nolibc/sysroot/riscv/include/arch.h:196: Error: unrecognized opcode `sd a2,%lo(environ)(a3)'

Refer to arch/riscv/include/asm/asm.h and add REG_L/REG_S macros here to let
rv32 uses its own lw/sw instructions.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
tools/include/nolibc/arch-riscv.h | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
index 0d5f15fdedc4..992a1739dd9c 100644
--- a/tools/include/nolibc/arch-riscv.h
+++ b/tools/include/nolibc/arch-riscv.h
@@ -33,9 +33,13 @@ struct sys_stat_struct {
#if __riscv_xlen == 64
#define PTRLOG "3"
#define SZREG "8"
+#define REG_L "ld"
+#define REG_S "sd"
#elif __riscv_xlen == 32
#define PTRLOG "2"
#define SZREG "4"
+#define REG_L "lw"
+#define REG_S "sw"
#endif

/* Syscalls for RISCV :
@@ -181,7 +185,7 @@ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
".option norelax\n"
"lla gp, __global_pointer$\n"
".option pop\n"
- "lw a0, 0(sp)\n" /* argc (a0) was in the stack */
+ REG_L" a0, 0(sp)\n" /* argc (a0) was in the stack */
"add a1, sp, "SZREG"\n" /* argv (a1) = sp */
"slli a2, a0, "PTRLOG"\n" /* envp (a2) = SZREG*argc ... */
"add a2, a2, "SZREG"\n" /* + SZREG (skip null) */
@@ -189,14 +193,14 @@ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)

"add a3, a2, zero\n" /* iterate a3 over envp to find auxv (after NULL) */
"0:\n" /* do { */
- "ld a4, 0(a3)\n" /* a4 = *a3; */
+ REG_L" a4, 0(a3)\n" /* a4 = *a3; */
"add a3, a3, "SZREG"\n" /* a3 += sizeof(void*); */
"bne a4, zero, 0b\n" /* } while (a4); */
"lui a4, %hi(_auxv)\n" /* a4 = &_auxv (high bits) */
- "sd a3, %lo(_auxv)(a4)\n" /* store a3 into _auxv */
+ REG_S" a3, %lo(_auxv)(a4)\n" /* store a3 into _auxv */

- "lui a3, %hi(environ)\n" /* a3 = &environ (high bits) */
- "sd a2,%lo(environ)(a3)\n" /* store envp(a2) into environ */
+ "lui a3, %hi(environ)\n" /* a3 = &environ (high bits) */
+ REG_S" a2,%lo(environ)(a3)\n"/* store envp(a2) into environ */
"andi sp,a1,-16\n" /* sp must be 16-byte aligned */
"call main\n" /* main() returns the status code, we'll exit with it. */
"li a7, 93\n" /* NR_exit == 93 */
--
2.40.1