Add several CFG-stress-testing input source files. These use the
preprocessor to build up very large CFGs in various shapes that can
produce different algorithmic behavior in CFG-walking code.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@134698 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/INPUTS/cfg-big-switch.c b/INPUTS/cfg-big-switch.c
new file mode 100644
index 0000000..a48b51a
--- /dev/null
+++ b/INPUTS/cfg-big-switch.c
@@ -0,0 +1,27 @@
+#define EXPAND_2_CASES(i, x, y) CASE(i, x, y); CASE(i + 1, x, y);
+#define EXPAND_4_CASES(i, x, y) EXPAND_2_CASES(i, x, y) EXPAND_2_CASES(i + 2, x, y)
+#define EXPAND_8_CASES(i, x, y) EXPAND_4_CASES(i, x, y) EXPAND_4_CASES(i + 4, x, y)
+#define EXPAND_16_CASES(i, x, y) EXPAND_8_CASES(i, x, y) EXPAND_8_CASES(i + 8, x, y)
+#define EXPAND_32_CASES(i, x, y) EXPAND_16_CASES(i, x, y) EXPAND_16_CASES(i + 16, x, y)
+#define EXPAND_64_CASES(i, x, y) EXPAND_32_CASES(i, x, y) EXPAND_32_CASES(i + 32, x, y)
+#define EXPAND_128_CASES(i, x, y) EXPAND_64_CASES(i, x, y) EXPAND_64_CASES(i + 64, x, y)
+#define EXPAND_256_CASES(i, x, y) EXPAND_128_CASES(i, x, y) EXPAND_128_CASES(i + 128, x, y)
+#define EXPAND_512_CASES(i, x, y) EXPAND_256_CASES(i, x, y) EXPAND_256_CASES(i + 256, x, y)
+#define EXPAND_1024_CASES(i, x, y) EXPAND_512_CASES(i, x, y) EXPAND_512_CASES(i + 512, x, y)
+#define EXPAND_2048_CASES(i, x, y) EXPAND_1024_CASES(i, x, y) EXPAND_1024_CASES(i + 1024, x, y)
+#define EXPAND_4096_CASES(i, x, y) EXPAND_2048_CASES(i, x, y) EXPAND_2048_CASES(i + 2048, x, y)
+
+// This has a *monstrous* single fan-out in the CFG, across 8000 blocks inside
+// the while loop.
+unsigned cfg_big_switch(int x) {
+ unsigned y = 0;
+ while (x > 0) {
+ switch(x) {
+#define CASE(i, x, y) \
+ case i: { int case_var = 3*x + i; y += case_var - 1; break; }
+EXPAND_4096_CASES(0, x, y);
+ }
+ --x;
+ }
+ return y;
+}