Add uadd_overflow_trap (#5123)

Add a new instruction uadd_overflow_trap, which is a fused version of iadd_ifcout and trapif. Adding this instruction removes a dependency on the iflags type, and would allow us to move closer to removing it entirely.

The instruction is defined for the i32 and i64 types only, and is currently only used in the legalization of heap_addr.

cranelift/filetests/filetests/isa/aarch64/uadd_overflow_trap.clif

@@ -0,0 +1,77 @@
+test compile precise-output
+target aarch64
+
+function %f0(i32) -> i32 {
+block0(v0: i32):
+    v1 = iconst.i32 127
+    v2 = uadd_overflow_trap v0, v1, user0
+    return v2
+}
+
+; block0:
+;   movz x3, #127
+;   adds w0, w0, w3
+;   b.lo 8 ; udf
+;   ret
+
+function %f1(i32) -> i32 {
+block0(v0: i32):
+    v1 = iconst.i32 127
+    v2 = uadd_overflow_trap v1, v0, user0
+    return v2
+}
+
+; block0:
+;   movz x3, #127
+;   adds w0, w3, w0
+;   b.lo 8 ; udf
+;   ret
+
+function %f2(i32, i32) -> i32 {
+block0(v0: i32, v1: i32):
+    v2 = uadd_overflow_trap v0, v1, user0
+    return v2
+}
+
+; block0:
+;   adds w0, w0, w1
+;   b.lo 8 ; udf
+;   ret
+
+function %f3(i64) -> i64 {
+block0(v0: i64):
+    v1 = iconst.i64 127
+    v2 = uadd_overflow_trap v0, v1, user0
+    return v2
+}
+
+; block0:
+;   movz x3, #127
+;   adds x0, x0, x3
+;   b.lo 8 ; udf
+;   ret
+
+function %f3(i64) -> i64 {
+block0(v0: i64):
+    v1 = iconst.i64 127
+    v2 = uadd_overflow_trap v1, v0, user0
+    return v2
+}
+
+; block0:
+;   movz x3, #127
+;   adds x0, x3, x0
+;   b.lo 8 ; udf
+;   ret
+
+function %f4(i64, i64) -> i64 {
+block0(v0: i64, v1: i64):
+    v2 = uadd_overflow_trap v0, v1, user0
+    return v2
+}
+
+; block0:
+;   adds x0, x0, x1
+;   b.lo 8 ; udf
+;   ret
+