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| author | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-07-28 10:39:49 +0200 |
|---|---|---|
| committer | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-08-06 17:43:37 +0200 |
| commit | 6da6517086e523f25cef070f9a89105f43147896 (patch) | |
| tree | 741717dc0c4844bd2ac7f6e2efdc3303cf79d0f0 | |
| parent | e3a5d3631fc2ba949fa5ba3c6d7b02387da2cf32 (diff) | |
| download | sparse-dev-6da6517086e523f25cef070f9a89105f43147896.tar.gz | |
limit the mask used for bitfield insertion
The mask used for bitfield insertion is as big as the integers
used internally by sparse. Elsewhere in the code, constants are
always truncated to the size of the instructions using them.
It's also displaying concerned instructions oddly. For example:
and.32 %r2 <- %r1, 0xfffffffffffffff0
Fix this by limiting the mask to the size of the instruction.
Fixes: a8e1df573 ("bitfield: extract linearize_bitfield_insert()")
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
| -rw-r--r-- | linearize.c | 3 | ||||
| -rw-r--r-- | validation/linear/bitfield-size.c | 12 |
2 files changed, 8 insertions, 7 deletions
diff --git a/linearize.c b/linearize.c index 17497186..c2010c4b 100644 --- a/linearize.c +++ b/linearize.c @@ -972,13 +972,14 @@ static pseudo_t linearize_bitfield_insert(struct entrypoint *ep, unsigned int shift = ctype->bit_offset; unsigned int size = ctype->bit_size; unsigned long long mask = ((1ULL << size) - 1); + unsigned long long smask= bits_mask(btype->bit_size); val = add_cast(ep, btype, ctype, OP_ZEXT, val); if (shift) { val = add_binary_op(ep, btype, OP_SHL, val, value_pseudo(shift)); mask <<= shift; } - ori = add_binary_op(ep, btype, OP_AND, ori, value_pseudo(~mask)); + ori = add_binary_op(ep, btype, OP_AND, ori, value_pseudo(~mask & smask)); val = add_binary_op(ep, btype, OP_OR, ori, val); return val; diff --git a/validation/linear/bitfield-size.c b/validation/linear/bitfield-size.c index 963f6e28..7f9725f9 100644 --- a/validation/linear/bitfield-size.c +++ b/validation/linear/bitfield-size.c @@ -52,7 +52,7 @@ upostinc: add.3 %r4 <- %r3, $1 load.32 %r5 <- 0[%r1] zext.32 %r6 <- (3) %r4 - and.32 %r7 <- %r5, $-8 + and.32 %r7 <- %r5, $0xfffffff8 or.32 %r8 <- %r7, %r6 store.32 %r8 -> 0[%r1] zext.32 %r9 <- (3) %r3 @@ -74,7 +74,7 @@ upreinc: add.3 %r14 <- %r13, $1 load.32 %r15 <- 0[%r11] zext.32 %r16 <- (3) %r14 - and.32 %r17 <- %r15, $-8 + and.32 %r17 <- %r15, $0xfffffff8 or.32 %r18 <- %r17, %r16 store.32 %r18 -> 0[%r11] zext.32 %r19 <- (3) %r14 @@ -97,7 +97,7 @@ ucpy: load.64 %r24 <- 0[d] load.32 %r25 <- 0[%r24] zext.32 %r26 <- (3) %r23 - and.32 %r27 <- %r25, $-8 + and.32 %r27 <- %r25, $0xfffffff8 or.32 %r28 <- %r27, %r26 store.32 %r28 -> 0[%r24] br .L5 @@ -116,7 +116,7 @@ spostinc: add.3 %r32 <- %r31, $1 load.32 %r33 <- 0[%r29] zext.32 %r34 <- (3) %r32 - and.32 %r35 <- %r33, $-8 + and.32 %r35 <- %r33, $0xfffffff8 or.32 %r36 <- %r35, %r34 store.32 %r36 -> 0[%r29] zext.32 %r37 <- (3) %r31 @@ -138,7 +138,7 @@ spreinc: add.3 %r42 <- %r41, $1 load.32 %r43 <- 0[%r39] zext.32 %r44 <- (3) %r42 - and.32 %r45 <- %r43, $-8 + and.32 %r45 <- %r43, $0xfffffff8 or.32 %r46 <- %r45, %r44 store.32 %r46 -> 0[%r39] zext.32 %r47 <- (3) %r42 @@ -161,7 +161,7 @@ scpy: load.64 %r52 <- 0[d] load.32 %r53 <- 0[%r52] zext.32 %r54 <- (3) %r51 - and.32 %r55 <- %r53, $-8 + and.32 %r55 <- %r53, $0xfffffff8 or.32 %r56 <- %r55, %r54 store.32 %r56 -> 0[%r52] br .L11 |