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-rw-r--r--js/src/jit-test/tests/sunspider/check-bitops-3bit-bits-in-byte.js35
1 files changed, 35 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/sunspider/check-bitops-3bit-bits-in-byte.js b/js/src/jit-test/tests/sunspider/check-bitops-3bit-bits-in-byte.js
new file mode 100644
index 0000000000..39bf060d02
--- /dev/null
+++ b/js/src/jit-test/tests/sunspider/check-bitops-3bit-bits-in-byte.js
@@ -0,0 +1,35 @@
+// Copyright (c) 2004 by Arthur Langereis (arthur_ext at domain xfinitegames, tld com
+
+// 1 op = 6 ANDs, 3 SHRs, 3 SHLs, 4 assigns, 2 ADDs
+// O(1)
+function fast3bitlookup(b) {
+var c, bi3b = 0xE994; // 0b1110 1001 1001 0100; // 3 2 2 1 2 1 1 0
+c = 3 & (bi3b >> ((b << 1) & 14));
+c += 3 & (bi3b >> ((b >> 2) & 14));
+c += 3 & (bi3b >> ((b >> 5) & 6));
+return c;
+
+/*
+lir4,0xE994; 9 instructions, no memory access, minimal register dependence, 6 shifts, 2 adds, 1 inline assign
+rlwinmr5,r3,1,28,30
+rlwinmr6,r3,30,28,30
+rlwinmr7,r3,27,29,30
+rlwnmr8,r4,r5,30,31
+rlwnmr9,r4,r6,30,31
+rlwnmr10,r4,r7,30,31
+addr3,r8,r9
+addr3,r3,r10
+*/
+}
+
+var ret = 0;
+function TimeFunc(func) {
+ var x, y, t;
+ for(var x=0; x<500; x++)
+ for(var y=0; y<256; y++) {
+ ret += func(y);
+ }
+}
+
+TimeFunc(fast3bitlookup);
+assertEq(ret, 512000)