From 0f64b8f696273bebcad25ed7294078c125811704 Mon Sep 17 00:00:00 2001 From: Richard Kenner Date: Sun, 7 Aug 1994 08:51:35 -0400 Subject: [PATCH] (qty_changes_size): New variable. (alloc_qty{,_for_scratch}, update_qty_class): Set it. (local_alloc): Allocate it. (find_free_reg): If CLASS_CANNOT_CHANGE_SIZE, avoid its registers if qty_changes_size. From-SVN: r7865 --- gcc/local-alloc.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/gcc/local-alloc.c b/gcc/local-alloc.c index 3b2d81ecf9b..f7774e0e751 100644 --- a/gcc/local-alloc.c +++ b/gcc/local-alloc.c @@ -165,6 +165,11 @@ static enum reg_class *qty_alternate_class; static rtx *qty_scratch_rtx; +/* Element Q is nonzero if this quantity has been used in a SUBREG + that changes its size. */ + +static char *qty_changes_size; + /* Element Q is the register number of one pseudo register whose reg_qty value is Q, or -1 is this quantity is for a SCRATCH. This register should be the head of the chain maintained in reg_next_in_qty. */ @@ -289,6 +294,7 @@ alloc_qty (regno, mode, size, birth) qty_min_class[qty] = reg_preferred_class (regno); qty_alternate_class[qty] = reg_alternate_class (regno); qty_n_refs[qty] = reg_n_refs[regno]; + qty_changes_size[qty] = reg_changes_size[regno]; } /* Similar to `alloc_qty', but allocates a quantity for a SCRATCH rtx @@ -378,6 +384,7 @@ alloc_qty_for_scratch (scratch, n, insn, insn_code_num, insn_number) qty_min_class[qty] = class; qty_alternate_class[qty] = NO_REGS; qty_n_refs[qty] = 1; + qty_changes_size[qty] = 0; } /* Main entry point of this file. */ @@ -439,6 +446,7 @@ local_alloc () qty_alternate_class = (enum reg_class *) alloca (max_qty * sizeof (enum reg_class)); qty_n_refs = (int *) alloca (max_qty * sizeof (int)); + qty_changes_size = (char *) alloca (max_qty * sizeof (char)); reg_qty = (int *) alloca (max_regno * sizeof (int)); reg_offset = (char *) alloca (max_regno * sizeof (char)); @@ -1925,6 +1933,9 @@ update_qty_class (qty, reg) rclass = reg_alternate_class (reg); if (reg_class_subset_p (rclass, qty_alternate_class[qty])) qty_alternate_class[qty] = rclass; + + if (reg_changes_size[reg]) + qty_changes_size[qty] = 1; } /* Handle something which alters the value of an rtx REG. @@ -2108,6 +2119,12 @@ find_free_reg (class, mode, qty, accept_call_clobbered, just_try_suggested, SET_HARD_REG_BIT (used, FRAME_POINTER_REGNUM); #endif +#ifdef CLASS_CANNOT_CHANGE_SIZE + if (qty_changes_size[qty]) + IOR_HARD_REG_SET (first_used, + reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE]); +#endif + /* Normally, the registers that can be used for the first register in a multi-register quantity are the same as those that can be used for subsequent registers. However, if just trying suggested registers,