From 15941d29c876e99179d1184c82100edc6dde4d2a Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 17 Feb 1998 13:54:24 -0800 Subject: [PATCH] combine.c (simplify_rtx): Obey CLASS_CANNOT_CHANGE_SIZE when simplifying a subreg of a hard reg. * combine.c (simplify_rtx): Obey CLASS_CANNOT_CHANGE_SIZE when simplifying a subreg of a hard reg. (expand_compound_operation): Likewise. (force_to_mode): Likewise. From-SVN: r18052 --- gcc/ChangeLog | 7 +++++++ gcc/combine.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 3733a2ad7202..757b6aa01875 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +Tue Feb 17 22:56:14 1998 Richard Henderson + + * combine.c (simplify_rtx): Obey CLASS_CANNOT_CHANGE_SIZE when + simplifying a subreg of a hard reg. + (expand_compound_operation): Likewise. + (force_to_mode): Likewise. + Tue Feb 17 22:37:22 1998 Kaveh R. Ghazi * Makefile.in (gcc.o): Depend on system.h, in accordance with last diff --git a/gcc/combine.c b/gcc/combine.c index 81f4d9bb6e21..dc8cc63853c3 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -3483,6 +3483,13 @@ simplify_rtx (x, op0_mode, last, in_dest) if (GET_CODE (SUBREG_REG (x)) == REG && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER +#ifdef CLASS_CANNOT_CHANGE_SIZE + && (! (TEST_HARD_REG_BIT + (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE], + REGNO (SUBREG_REG (x)))) + || (GET_MODE_SIZE (mode) + == GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))) +#endif && REGNO (SUBREG_REG (x)) != FRAME_POINTER_REGNUM #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM && REGNO (SUBREG_REG (x)) != HARD_FRAME_POINTER_REGNUM @@ -5106,6 +5113,20 @@ expand_compound_operation (x) int modewidth; rtx tem; +#ifdef CLASS_CANNOT_CHANGE_SIZE + /* When dealing with hard regs that cannot change size, don't even try + expanding to shifts, since we wind up violating the rule. */ + if (GET_RTX_CLASS (GET_CODE (x)) == '1' + && GET_CODE (XEXP (x, 0)) == REG + && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER + && (TEST_HARD_REG_BIT + (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE], + REGNO (SUBREG_REG (x)))) + && (GET_MODE_SIZE (GET_MODE (x)) + != GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))) + return x; +#endif + switch (GET_CODE (x)) { case ZERO_EXTEND: @@ -6222,6 +6243,17 @@ force_to_mode (x, mode, mask, reg, just_select) break; case SUBREG: +#ifdef CLASS_CANNOT_CHANGE_SIZE + if (GET_CODE (SUBREG_REG (x)) == REG + && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER + && (TEST_HARD_REG_BIT + (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE], + REGNO (SUBREG_REG (x)))) + && (GET_MODE_SIZE (GET_MODE (x)) + != GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))) + return x; +#endif + if (subreg_lowpart_p (x) /* We can ignore the effect of this SUBREG if it narrows the mode or if the constant masks to zero all the bits the mode doesn't -- 2.47.3