arm64: Improve constant generation, with tests.

Edmund Grimley Evans committed 11 years ago

Commit 86e8dcd1 parent 883fd363 files · +55 −8Browse files

Unified · Split

3 files

@@ -204,16 +204,30 @@ static void arm64_movimm(int r, uint64_t x) · 203 unmodified lines
204	204	{
205	205	uint32_t i;
206	206	if ((i = arm64_movi(r, x)))
207		− o(i);
	207	+ o(i); // a single MOV
208	208	else {
209		− // This could be improved:
210		− o(0x52800000 \| r \| (x & 0xffff) << 5); // movz w(r),#(x & 0xffff)
211		− for (i = 1; i < 4; i++)
212		− if (x >> 16 * i & 0xffff) {
213		− o(0xf2800000 \| r \| (x >> 16 * i & 0xffff) << 5 \| i << 21);
214		− // movk w(r),#(),lsl #()
	209	+ // MOVZ/MOVN and 1-3 MOVKs
	210	+ int z = 0, m = 0;
	211	+ uint32_t mov1 = 0xd2800000; // movz
	212	+ uint64_t x1 = x;
	213	+ for (i = 0; i < 64; i += 16) {
	214	+ z += !(x >> i & 0xffff);
	215	+ m += !(~x >> i & 0xffff);
	216	+ }
	217	+ if (m > z) {
	218	+ x1 = ~x;
	219	+ mov1 = 0x92800000; // movn
	220	+ }
	221	+ for (i = 0; i < 64; i += 16)
	222	+ if (x1 >> i & 0xffff) {
	223	+ o(mov1 \| r \| (x1 >> i & 0xffff) << 5 \| i << 17);
	224	+ // movz/movn x(r),#(*),lsl #(i)
	225	+ break;
215	226	}
216		−
	227	+ for (i += 16; i < 64; i += 16)
	228	+ if (x1 >> i & 0xffff)
	229	+ o(0xf2800000 \| r \| (x >> i & 0xffff) << 5 \| i << 17);
	230	+ // movk x(r),#(*),lsl #(i)
217	231	}
218	232	}
219	233

@@ -409,6 +409,24 @@ void movi(void) · 408 unmodified lines
409	409	pll(0x007fffc0);
410	410	pll(0x03fff80003fff800);
411	411	pll(0x0007fffffffffe00);
	412	+
	413	+ pll(0xabcd1234);
	414	+ pll(0xabcd00001234);
	415	+ pll(0xabcd000000001234);
	416	+ pll(0xabcd12340000);
	417	+ pll(0xabcd000012340000);
	418	+ pll(0xabcd123400000000);
	419	+ pll(0xffffffffabcd1234);
	420	+ pll(0xffffabcdffff1234);
	421	+ pll(0xabcdffffffff1234);
	422	+ pll(0xffffabcd1234ffff);
	423	+ pll(0xabcdffff1234ffff);
	424	+ pll(0xabcd1234ffffffff);
	425	+
	426	+ pll(0xffffef0123456789);
	427	+ pll(0xabcdef012345ffff);
	428	+
	429	+ pll(0xabcdef0123456789);
412	430	}
413	431
414	432	void pcs(void)

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