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| author | Richard Earnshaw <rearnsha@arm.com> | 2009-06-02 07:47:09 +0000 |
|---|---|---|
| committer | Richard Earnshaw <rearnsha@gcc.gnu.org> | 2009-06-02 07:47:09 +0000 |
| commit | 55b2829b99458634704698462459784bd324aea8 (patch) | |
| tree | 345e54150acca6ed4c32ab4c6ba829ae98672436 /gcc/config/arm | |
| parent | 18d6353c18fbf62f20bd1bff4a8fd734c01b21bc (diff) | |
| download | gcc-55b2829b99458634704698462459784bd324aea8.zip gcc-55b2829b99458634704698462459784bd324aea8.tar.gz gcc-55b2829b99458634704698462459784bd324aea8.tar.bz2 | |
arm.c (arm_get_frame_offsets): Prefer using r3 for padding a push/pop multiple to 8-byte alignment.
* arm.c (arm_get_frame_offsets): Prefer using r3 for padding a
push/pop multiple to 8-byte alignment.
From-SVN: r148072
Diffstat (limited to 'gcc/config/arm')
| -rw-r--r-- | gcc/config/arm/arm.c | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 8ae8dab..24a94a6 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -12822,22 +12822,23 @@ arm_get_frame_offsets (void) { int reg = -1; - for (i = 4; i <= (TARGET_THUMB1 ? LAST_LO_REGNUM : 11); i++) + /* If it is safe to use r3, then do so. This sometimes + generates better code on Thumb-2 by avoiding the need to + use 32-bit push/pop instructions. */ + if (!crtl->tail_call_emit + && arm_size_return_regs () <= 12) { - if ((offsets->saved_regs_mask & (1 << i)) == 0) - { - reg = i; - break; - } - } - - if (reg == -1 && arm_size_return_regs () <= 12 - && !crtl->tail_call_emit) - { - /* Push/pop an argument register (r3) if all callee saved - registers are already being pushed. */ reg = 3; } + else + for (i = 4; i <= (TARGET_THUMB1 ? LAST_LO_REGNUM : 11); i++) + { + if ((offsets->saved_regs_mask & (1 << i)) == 0) + { + reg = i; + break; + } + } if (reg != -1) { |