Initial support for __mulhi3

2026-04-20 11:17:18 +00:00 · 2021-05-19 21:34:33 -06:00
parent 468e794d5e
commit 49cf9cc32d
3 changed files with 61 additions and 3321 deletions
@@ -0,0 +1,35 @@
+
+static constexpr std::string_view __mulhi3 = 
+R"(
+;;; based on protocol from gcc's calling conventions for AVR
+
+;;; R25:R24 = R23:R22 * R25:R24
+;;; Clobbers: __tmp_reg__, R21..R23
+
+__mulhi3:
+        mov __temp_reg__,r24
+        mov r21,r25
+        ldi r25,0
+        ldi r24,0
+        cp __temp_reg__,__zero_reg__
+        cpc r21,__zero_reg__
+        breq .__mulhi3_L5
+.__mulhi3_L4:
+        sbrs __temp_reg__,0
+        rjmp .__mulhi3_L3
+        add r24,r22
+        adc r25,r23
+.__mulhi3_L3:
+        lsr r21
+        ror __temp_reg__
+        lsl r22
+        rol r23
+        cp __temp_reg__,__zero_reg__
+        cpc r21,__zero_reg__
+        brne .__mulhi3_L4
+        ret
+.__mulhi3_L5:
+        ret
+)";
+
+