Patchwork target-arm: Fix TCG temp handling in 64 bit cp writes

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Submitter Peter Maydell
Date July 5, 2012, 11:32 a.m.
Message ID <1341487947-21760-1-git-send-email-peter.maydell@linaro.org>
Download mbox | patch
Permalink /patch/169124/
State New
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Comments

Peter Maydell - July 5, 2012, 11:32 a.m.
Fix errors in the TCG temp handling in the 64 bit coprocessor
write path: we were reusing a 32 bit temp after it had been
freed by store_reg(), and failing to free a 64 bit temp.

This bug has no visible effect at this point because there
aren't any non-NOP 64 bit registers yet; it needs to be fixed
as a prerequisite for the 64 bit registers in LPAE support.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
I didn't notice this with my earlier LPAE testing because
(a) I wasn't testing with an --enable-debug build and
(b) it only caused an actual problem when passing more than
512MB of RAM to the LPAE guest...

 target-arm/translate.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

Patch

diff --git a/target-arm/translate.c b/target-arm/translate.c
index a2a0ecd..64d7cfd 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -6263,7 +6263,9 @@  static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
                 tcg_gen_trunc_i64_i32(tmp, tmp64);
                 store_reg(s, rt, tmp);
                 tcg_gen_shri_i64(tmp64, tmp64, 32);
+                tmp = tcg_temp_new_i32();
                 tcg_gen_trunc_i64_i32(tmp, tmp64);
+                tcg_temp_free_i64(tmp64);
                 store_reg(s, rt2, tmp);
             } else {
                 TCGv tmp;