+// Odd encoding trick: -128 fits into an 8-bit immediate field while
+// +128 doesn't, so in this special case use a sub instead of an add.
+def : Pat<(add GR64:$src1, 128),
+ (SUB64ri8 GR64:$src1, -128)>;
+def : Pat<(store (add (loadi64 addr:$dst), 128), addr:$dst),
+ (SUB64mi8 addr:$dst, -128)>;
+
+// The same trick applies for 32-bit immediate fields in 64-bit
+// instructions.
+def : Pat<(add GR64:$src1, 0x0000000080000000),
+ (SUB64ri32 GR64:$src1, 0xffffffff80000000)>;
+def : Pat<(store (add (loadi64 addr:$dst), 0x00000000800000000), addr:$dst),
+ (SUB64mi32 addr:$dst, 0xffffffff80000000)>;
+
+// r & (2^32-1) ==> movz
+def : Pat<(and GR64:$src, 0x00000000FFFFFFFF),
+ (MOVZX64rr32 (EXTRACT_SUBREG GR64:$src, x86_subreg_32bit))>;
+// r & (2^16-1) ==> movz
+def : Pat<(and GR64:$src, 0xffff),
+ (MOVZX64rr16 (i16 (EXTRACT_SUBREG GR64:$src, x86_subreg_16bit)))>;
+// r & (2^8-1) ==> movz
+def : Pat<(and GR64:$src, 0xff),
+ (MOVZX64rr8 (i8 (EXTRACT_SUBREG GR64:$src, x86_subreg_8bit)))>;
+// r & (2^8-1) ==> movz
+def : Pat<(and GR32:$src1, 0xff),
+ (MOVZX32rr8 (EXTRACT_SUBREG GR32:$src1, x86_subreg_8bit))>,
+ Requires<[In64BitMode]>;
+// r & (2^8-1) ==> movz
+def : Pat<(and GR16:$src1, 0xff),
+ (MOVZX16rr8 (i8 (EXTRACT_SUBREG GR16:$src1, x86_subreg_8bit)))>,
+ Requires<[In64BitMode]>;
+
+// sext_inreg patterns
+def : Pat<(sext_inreg GR64:$src, i32),
+ (MOVSX64rr32 (EXTRACT_SUBREG GR64:$src, x86_subreg_32bit))>;
+def : Pat<(sext_inreg GR64:$src, i16),
+ (MOVSX64rr16 (EXTRACT_SUBREG GR64:$src, x86_subreg_16bit))>;
+def : Pat<(sext_inreg GR64:$src, i8),
+ (MOVSX64rr8 (EXTRACT_SUBREG GR64:$src, x86_subreg_8bit))>;
+def : Pat<(sext_inreg GR32:$src, i8),
+ (MOVSX32rr8 (EXTRACT_SUBREG GR32:$src, x86_subreg_8bit))>,
+ Requires<[In64BitMode]>;
+def : Pat<(sext_inreg GR16:$src, i8),
+ (MOVSX16rr8 (i8 (EXTRACT_SUBREG GR16:$src, x86_subreg_8bit)))>,
+ Requires<[In64BitMode]>;
+
+// trunc patterns
+def : Pat<(i32 (trunc GR64:$src)),
+ (EXTRACT_SUBREG GR64:$src, x86_subreg_32bit)>;
+def : Pat<(i16 (trunc GR64:$src)),
+ (EXTRACT_SUBREG GR64:$src, x86_subreg_16bit)>;
+def : Pat<(i8 (trunc GR64:$src)),
+ (EXTRACT_SUBREG GR64:$src, x86_subreg_8bit)>;
+def : Pat<(i8 (trunc GR32:$src)),
+ (EXTRACT_SUBREG GR32:$src, x86_subreg_8bit)>,
+ Requires<[In64BitMode]>;
+def : Pat<(i8 (trunc GR16:$src)),
+ (EXTRACT_SUBREG GR16:$src, x86_subreg_8bit)>,
+ Requires<[In64BitMode]>;
+
+// h-register tricks.
+// For now, be conservative on x86-64 and use an h-register extract only if the
+// value is immediately zero-extended or stored, which are somewhat common
+// cases. This uses a bunch of code to prevent a register requiring a REX prefix
+// from being allocated in the same instruction as the h register, as there's
+// currently no way to describe this requirement to the register allocator.
+
+// h-register extract and zero-extend.
+def : Pat<(and (srl_su GR64:$src, (i8 8)), (i64 255)),
+ (SUBREG_TO_REG
+ (i64 0),
+ (MOVZX32_NOREXrr8
+ (EXTRACT_SUBREG (COPY_TO_REGCLASS GR64:$src, GR64_ABCD),
+ x86_subreg_8bit_hi)),
+ x86_subreg_32bit)>;
+def : Pat<(and (srl_su GR32:$src, (i8 8)), (i32 255)),
+ (MOVZX32_NOREXrr8
+ (EXTRACT_SUBREG (COPY_TO_REGCLASS GR32:$src, GR32_ABCD),
+ x86_subreg_8bit_hi))>,
+ Requires<[In64BitMode]>;
+def : Pat<(srl_su GR16:$src, (i8 8)),
+ (EXTRACT_SUBREG
+ (MOVZX32_NOREXrr8
+ (EXTRACT_SUBREG (COPY_TO_REGCLASS GR16:$src, GR16_ABCD),
+ x86_subreg_8bit_hi)),
+ x86_subreg_16bit)>,
+ Requires<[In64BitMode]>;
+def : Pat<(i32 (zext (srl_su GR16:$src, (i8 8)))),
+ (MOVZX32_NOREXrr8
+ (EXTRACT_SUBREG (COPY_TO_REGCLASS GR16:$src, GR16_ABCD),
+ x86_subreg_8bit_hi))>,
+ Requires<[In64BitMode]>;
+def : Pat<(i64 (zext (srl_su GR16:$src, (i8 8)))),
+ (SUBREG_TO_REG
+ (i64 0),
+ (MOVZX32_NOREXrr8
+ (EXTRACT_SUBREG (COPY_TO_REGCLASS GR16:$src, GR16_ABCD),
+ x86_subreg_8bit_hi)),