py/emitinlinerv32: Add inline assembler support for RV32.

This commit adds support for writing inline assembler functions when
targeting a RV32IMC processor.

Given that this takes up a bit of rodata space due to its large
instruction decoding table and its extensive error messages, it is
enabled by default only on offline targets such as mpy-cross and the
qemu port.

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

1 files changed, 65 insertions, 0 deletions

diff --git a/tests/inlineasm/rv32/asmstack.py b/tests/inlineasm/rv32/asmstack.py
new file mode 100644
index 000000000..9035f8728
--- /dev/null
+++ b/tests/inlineasm/rv32/asmstack.py
@@ -0,0 +1,65 @@
+# test stack manipulation
+
+
+@micropython.asm_rv32
+def l():
+    li(a2, 3)
+    addi(sp, sp, -8)
+    li(a0, 0x123)
+    sw(a0, 0(sp))
+    addi(a1, a0, 0x111)
+    sw(a1, 4(sp))
+    c_lwsp(a3, 0)
+    bne(a3, a0, END)
+    addi(a2, a2, -1)
+    c_lwsp(a3, 4)
+    bne(a3, a1, END)
+    addi(a2, a2, -1)
+    label(END)
+    addi(sp, sp, 8)
+    mv(a0, a2)
+
+
+print(l())
+
+
+@micropython.asm_rv32
+def s():
+    li(a2, 3)
+    addi(sp, sp, -8)
+    li(a0, 0x123)
+    c_swsp(a0, 0)
+    addi(a1, a0, 0x111)
+    c_swsp(a1, 4)
+    lw(a3, 0(sp))
+    bne(a3, a0, END)
+    addi(a2, a2, -1)
+    lw(a3, 4(sp))
+    bne(a3, a1, END)
+    addi(a2, a2, -1)
+    label(END)
+    addi(sp, sp, 8)
+    mv(a0, a2)
+
+
+print(s())
+
+
+@micropython.asm_rv32
+def a():
+    li(a2, 3)
+    addi(sp, sp, -8)
+    li(a0, 0x123)
+    sw(a0, 0(sp))
+    addi(a1, a0, 0x111)
+    sw(a1, 4(sp))
+    c_addi4spn(a3, 4)
+    lw(a3, -4(a3))
+    bne(a3, a0, END)
+    addi(a2, a2, -1)
+    label(END)
+    addi(sp, sp, 8)
+    mv(a0, a2)
+
+
+print(a())