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 useing 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@xxxxxxxxx>
---
linearize.c | 3 ++-
validation/linear/bitfield-size.c | 12 ++++++------
2 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/linearize.c b/linearize.c
index ce68ba10a..ec3934a40 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 963f6e28b..7f9725f9d 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
--
2.18.0
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