github.com/euank/go@v0.0.0-20160829210321-495514729181/src/cmd/compile/internal/s390x/reg.go (about)

     1  // Derived from Inferno utils/6c/reg.c
     2  // https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6c/reg.c
     3  //
     4  //	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
     5  //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
     6  //	Portions Copyright © 1997-1999 Vita Nuova Limited
     7  //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
     8  //	Portions Copyright © 2004,2006 Bruce Ellis
     9  //	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
    10  //	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
    11  //	Portions Copyright © 2009 The Go Authors.  All rights reserved.
    12  //
    13  // Permission is hereby granted, free of charge, to any person obtaining a copy
    14  // of this software and associated documentation files (the "Software"), to deal
    15  // in the Software without restriction, including without limitation the rights
    16  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    17  // copies of the Software, and to permit persons to whom the Software is
    18  // furnished to do so, subject to the following conditions:
    19  //
    20  // The above copyright notice and this permission notice shall be included in
    21  // all copies or substantial portions of the Software.
    22  //
    23  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    24  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    25  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    26  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    27  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    28  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    29  // THE SOFTWARE.
    30  
    31  package s390x
    32  
    33  import "cmd/internal/obj/s390x"
    34  import "cmd/compile/internal/gc"
    35  
    36  const (
    37  	NREGVAR = 32 /* 16 general + 16 floating */
    38  )
    39  
    40  var regname = []string{
    41  	".R0",
    42  	".R1",
    43  	".R2",
    44  	".R3",
    45  	".R4",
    46  	".R5",
    47  	".R6",
    48  	".R7",
    49  	".R8",
    50  	".R9",
    51  	".R10",
    52  	".R11",
    53  	".R12",
    54  	".R13",
    55  	".R14",
    56  	".R15",
    57  	".F0",
    58  	".F1",
    59  	".F2",
    60  	".F3",
    61  	".F4",
    62  	".F5",
    63  	".F6",
    64  	".F7",
    65  	".F8",
    66  	".F9",
    67  	".F10",
    68  	".F11",
    69  	".F12",
    70  	".F13",
    71  	".F14",
    72  	".F15",
    73  }
    74  
    75  func regnames(n *int) []string {
    76  	*n = NREGVAR
    77  	return regname
    78  }
    79  
    80  func excludedregs() uint64 {
    81  	// Exclude registers with fixed functions
    82  	return RtoB(s390x.REG_R0) |
    83  		RtoB(s390x.REGSP) |
    84  		RtoB(s390x.REGG) |
    85  		RtoB(s390x.REGTMP) |
    86  		RtoB(s390x.REGTMP2) |
    87  		RtoB(s390x.REG_LR)
    88  }
    89  
    90  func doregbits(r int) uint64 {
    91  	return 0
    92  }
    93  
    94  /*
    95   * track register variables including external registers:
    96   *	bit	reg
    97   *	0	R0
    98   *	...	...
    99   *	15	R15
   100   *	16+0	F0
   101   *	16+1	F1
   102   *	...	...
   103   *	16+15	F15
   104   */
   105  func RtoB(r int) uint64 {
   106  	if r >= s390x.REG_R0 && r <= s390x.REG_R15 {
   107  		return 1 << uint(r-s390x.REG_R0)
   108  	}
   109  	if r >= s390x.REG_F0 && r <= s390x.REG_F15 {
   110  		return 1 << uint(16+r-s390x.REG_F0)
   111  	}
   112  	return 0
   113  }
   114  
   115  func BtoR(b uint64) int {
   116  	b &= 0xffff
   117  	if b == 0 {
   118  		return 0
   119  	}
   120  	return gc.Bitno(b) + s390x.REG_R0
   121  }
   122  
   123  func BtoF(b uint64) int {
   124  	b >>= 16
   125  	b &= 0xffff
   126  	if b == 0 {
   127  		return 0
   128  	}
   129  	return gc.Bitno(b) + s390x.REG_F0
   130  }