contrib/gcc/combine.c

1463 	 (set (subreg:SI (reg:DI 101) 0) <foo>)
1467 	 (parallel [(set (subreg:SI (reg:DI 100) 0) <foo>)
4055 		  /* In general, don't install a subreg involving two
4493 	 whose value is a comparison can be replaced with a subreg if
5386   /* If we have (set x (subreg:m1 (op:m2 ...) 0)) with OP being some operation,
5387      and X being a REG or (subreg (reg)), we may be able to convert this to
5388      (set (subreg:m2 x) (op)).
5427   /* If we have (set (cc0) (subreg ...)), we try to remove the subreg
5451   /* If we have (set FOO (subreg:M (mem:N BAR) 0)) with M wider than N, this
5452      would require a paradoxical subreg.  Replace the subreg with a
5647       /* Return if (subreg:MODE FROM 0) is not a safe replacement for
5746       /* Likewise for (zero_extend:DI (subreg:SI foo:DI 0)).  */
5768       /* Likewise for (zero_extend:DI (subreg:SI foo:DI 0)).  */
6000       /* If going from (subreg:SI (mem:QI ...)) to (mem:QI ...),
6002 	 The subreg adds or removes high bits; its mode is
6498       /* Same as previous, but for (subreg (lshiftrt ...)) in first op.  */
6832    MODE we can just return a subreg even though in the general case we
7705 	  /* We must simplify subreg here, before we lose track of the
8825 		 we have (ashift:M1 (subreg:M1 (ashiftrt:M2 FOO C1) 0) C2)
8828 		 (ashiftrt:M1 (ashift:M1 (and:M1 (subreg:M1 FOO 0 C2) C3) C1).
9476   /* X might be a paradoxical (subreg (mem)).  In that case, gen_lowpart
9514 	 generate a paradoxical subreg instead.  That will force a reload
10114 	       (subreg:MODE (plus (A) (-C1))) op (C2)
10409 	  /* If this is (and:M1 (subreg:M2 X 0) (const_int C1)) where C1
11124 record_promoted_value (rtx insn, rtx subreg)
11127   unsigned int regno = REGNO (SUBREG_REG (subreg));
11128   enum machine_mode mode = GET_MODE (subreg);
11140 	  || GET_MODE (SET_DEST (set)) != GET_MODE (SUBREG_REG (subreg)))
11148 	  if (SUBREG_PROMOTED_UNSIGNED_P (subreg) > 0)
11163    truncated to MODE.  In this case we can use a subreg to refer to
11184    a truncate into a subreg using this information.  */