moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

cranelift/filetests/filetests/regalloc/infinite-interference.clif

@@ -0,0 +1,37 @@
+test regalloc
+target riscv32
+
+; Here, the coalescer initially builds vreg0 = [v1, v2, v3]
+;
+; There's interference between v1 and v2 at the brz instruction. Isolating v2 is not going to
+; resolve that conflict since v1 will just interfere with the inserted copy too.
+
+;function %c1(i32) -> i32 {
+;ebb0(v0: i32):
+;    v1 = iadd_imm v0, 1
+;    v2 = iconst.i32 1
+;    brz v1, ebb1(v2)
+;    jump ebb2
+;
+;ebb1(v3: i32):
+;    return v3
+;
+;ebb2:
+;    jump ebb1(v1)
+;}
+
+; Same thing with v1 and v2 swapped to reverse the order of definitions.
+
+function %c2(i32) -> i32 {
+ebb0(v0: i32):
+    v1 = iadd_imm v0, 1
+    v2 = iconst.i32 1
+    brz v2, ebb1(v1)
+    jump ebb2
+
+ebb1(v3: i32):
+    return v3
+
+ebb2:
+    jump ebb1(v2)
+}