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| author | Stafford Horne <shorne@gmail.com> | 2019-08-31 06:00:56 +0000 |
|---|---|---|
| committer | Stafford Horne <shorne@gcc.gnu.org> | 2019-08-31 06:00:56 +0000 |
| commit | fd631eb5a7597a7040f770b2a912cec13af50df4 (patch) | |
| tree | 29306617e9d66d1e5b92c3832c3ab9d2e5d7a0f0 /gcc/config/or1k/constraints.md | |
| parent | 3ba155dd1921b55f04866b35a2e054e092670cd6 (diff) | |
| download | gcc-fd631eb5a7597a7040f770b2a912cec13af50df4.zip gcc-fd631eb5a7597a7040f770b2a912cec13af50df4.tar.gz gcc-fd631eb5a7597a7040f770b2a912cec13af50df4.tar.bz2 | |
or1k: Fix issue with set_got clobbering LR (r9)
When compiling glibc we found that the GOT register was being allocated
r9 when the instruction was still set_got_tmp. That is a problem
because r9 is the Link Register (LR) in OpenRISC which is used/clobbered
in set_got. We cannot use r9 as the GOT register. Also, we cannot
simply say set_got_tmp clobbers r9 as this is the reason for having the
temporary set_got_tmp.
Fix by using a register class constraint that does not allow r9 during
register allocation.
gcc/ChangeLog:
* config/or1k/constraints.md (t): New constraint.
* config/or1k/or1k.h (GOT_REGS): New register class.
* config/or1k/or1k.md (set_got_tmp, set_got): Use t contraint.
From-SVN: r275242
Diffstat (limited to 'gcc/config/or1k/constraints.md')
| -rw-r--r-- | gcc/config/or1k/constraints.md | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/gcc/config/or1k/constraints.md b/gcc/config/or1k/constraints.md index 8cac7eb..3ca477c 100644 --- a/gcc/config/or1k/constraints.md +++ b/gcc/config/or1k/constraints.md @@ -25,6 +25,7 @@ ; We use: ; c - sibcall registers ; d - double pair base registers (excludes r0, r30 and r31 which overflow) +; t - got address registers (excludes LR (r9) which is clobbered by set_got) ; I - constant signed 16-bit ; K - constant unsigned 16-bit ; M - constant signed 16-bit shifted left 16-bits (l.movhi) @@ -36,6 +37,9 @@ (define_register_constraint "d" "DOUBLE_REGS" "Registers which can be used for double reg pairs.") +(define_register_constraint "t" "GOT_REGS" + "Registers which can be used to store the Global Offset Table (GOT) address.") + ;; Immediates (define_constraint "I" "A signed 16-bit immediate in the range -32768 to 32767." |