From 59dbe1d9da8b946a0f652a02f6f439d6abf1bd5c Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Sat, 25 Oct 2008 15:49:27 +0000 Subject: [PATCH] mips.h (REG_ALLOC_ORDER): Put call-clobbered registers first. gcc/ * config/mips/mips.h (REG_ALLOC_ORDER): Put call-clobbered registers first. From-SVN: r141362 --- gcc/ChangeLog | 5 +++++ gcc/config/mips/mips.h | 32 +++++++++++++++++++++++++------- 2 files changed, 30 insertions(+), 7 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ec04a4d..44bb0e5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2008-10-25 Richard Sandiford + + * config/mips/mips.h (REG_ALLOC_ORDER): Put call-clobbered registers + first. + 2008-10-24 Michael Meissner PR target/37841 diff --git a/gcc/config/mips/mips.h b/gcc/config/mips/mips.h index acfcc00..ecf7d91 100644 --- a/gcc/config/mips/mips.h +++ b/gcc/config/mips/mips.h @@ -1913,16 +1913,34 @@ enum reg_class #define SMALL_REGISTER_CLASSES (TARGET_MIPS16) -/* REG_ALLOC_ORDER is to order in which to allocate registers. This - is the default value (allocate the registers in numeric order). We - define it just so that we can override it for the mips16 target in - ORDER_REGS_FOR_LOCAL_ALLOC. */ +/* We generally want to put call-clobbered registers ahead of + call-saved ones. (IRA expects this.) */ #define REG_ALLOC_ORDER \ -{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, \ - 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, \ +{ /* Call-clobbered GPRs. */ \ + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, \ + 24, 25, 31, \ + /* The global pointer. This is call-clobbered for o32 and o64 \ + abicalls, call-saved for n32 and n64 abicalls, and a program \ + invariant otherwise. Putting it between the call-clobbered \ + and call-saved registers should cope with all eventualities. */ \ + 28, \ + /* Call-saved GPRs. */ \ + 16, 17, 18, 19, 20, 21, 22, 23, 30, \ + /* GPRs that can never be exposed to the register allocator. */ \ + 0, 26, 27, 29, \ + /* Call-clobbered FPRs. */ \ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, \ - 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, \ + 48, 49, 50, 51, \ + /* FPRs that are usually call-saved. The odd ones are actually \ + call-clobbered for n32, but listing them ahead of the even \ + registers might encourage the register allocator to fragment \ + the available FPR pairs. We need paired FPRs to store long \ + doubles, so it isn't clear that using a different order \ + for n32 would be a win. */ \ + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, \ + /* None of the remaining classes have defined call-saved \ + registers. */ \ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, \ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, \ 96, 97, 98, 99, 100,101,102,103,104,105,106,107,108,109,110,111, \ -- 2.7.4