Merge change 24577 into eclair (374ad789) · Commits · e / os / android_system_core

libacc/acc.cpp

+48 −11

Original line number	Diff line number	Diff line
		@@ -730,6 +730,18 @@ class Compiler : public ErrorSink {
		return rotateRight(data, rotate);
		}

		static bool isPowerOfTwo(size_t n) {
		return (n != 0) & ((n & (n-1)) == 0);
		}

		static size_t log2(size_t n) {
		int result = 0;
		while (n >>= 1) {
		result++;
		}
		return result;
		}

		class ARMCodeBuf : public ICodeBuf {
		ICodeBuf* mpBase;
		ErrorSink* mErrorSink;
		@@ -825,8 +837,9 @@ class Compiler : public ErrorSink {
		// Peephole check
		bool didPeep;
		do {
		const unsigned int opMask = 0x01e00000;
		const unsigned int immediateMask = 0x00000fff;
		static const unsigned int opMask = 0x01e00000;
		static const unsigned int immediateMask = 0x00000fff;
		static const unsigned int BMask = 0x00400000;
		didPeep = false;
		if (mQ.count() >= 4) {

		@@ -853,16 +866,25 @@ class Compiler : public ErrorSink {
		}

		// Load local variable
		// sub r0,r11,#imm;ldr r0,[r0] ==> ldr r0, [r11,#-imm]
		// sub r0,r11,#imm;ldr/ldrb r0,[r0] ==> ldr/ldrb r0, [r11,#-imm]
		if (mQ.count() >= 2) {
		if ((mQ[-2] & ~immediateMask) == 0xe24b0000 && // sub r0,r11,#imm
		mQ[-1] == 0xe5900000) { // ldr r0, [r0]
		unsigned int op = mQ[-2];
		unsigned int ld = mQ[-1];
		unsigned int combined = (op & immediateMask) \| 0xE51B0000; // ldr r0, [r11, #-0]
		if ((mQ[-2] & ~immediateMask) == 0xe24b0000) { // sub r0,r11,#imm
		const unsigned int encodedImmediate = mQ[-2] & immediateMask;
		const unsigned int ld = mQ[-1];
		if ((ld & ~BMask) == 0xe5900000) { // ldr{b} r0, [r0]
		unsigned int combined = encodedImmediate \| (0xE51B0000 \| (ld & BMask)); // ldr r0, [r11, #-0]
		mQ.popBack(2);
		mQ.pushBack(combined);
		didPeep = true;
		} else if (ld == 0xedd07a00) { // ldcl p10, c7, [r0, #0x000]
		unsigned int decodedImmediate = decode12BitImmediate(encodedImmediate);
		if (decodedImmediate <= 1020 && ((decodedImmediate & 3) == 0)) {
		unsigned int combined = (decodedImmediate >> 2) \| 0xed5b7a00; // ldcl p10, c7, [r11, #-0]
		mQ.popBack(2);
		mQ.pushBack(combined);
		didPeep = true;
		}
		}
		}
		}

		@@ -891,6 +913,21 @@ class Compiler : public ErrorSink {
		}
		}

		// Pointer arithmetic with a stride that is a power of two

		if (mQ.count() >= 3 &&
		(mQ[-3] & ~ immediateMask) == 0xe3a02000 && // mov r2, #stride
		mQ[-2] == 0xe0000092 && // mul r0, r2, r0
		mQ[-1] == 0xe0810000) { // add r0, r1, r0
		int stride = decode12BitImmediate(mQ[-3]);
		if (isPowerOfTwo(stride)) {
		mQ.popBack(3);
		unsigned int add = 0xe0810000 \| (log2(stride) << 7); // add r0, r1, r0, LSL #log2(stride)
		mQ.pushBack(add);
		didPeep = true;
		}
		}

		} while (didPeep);
		#endif
		}