The boolean operators '||' and '&&' need to have their operands
first compared against zero. However, this is not needed if the
operands is already a boolean, for example because it's already
the result of another previous such operation.
For example, the following expression:
int a, b, c;
... a || b || c ...
is linearized and simplified to:
setne.1 %r2 <- %arg1, $0
setne.1 %r4 <- %arg2, $0
or-bool.1 %r5 <- %r2, %r4
setne.1 %r7 <- %r5, $0
setne.1 %r9 <- %arg3, $0
or-bool.1 %r10 <- %r7, %r9
but the 3rd 'setne' is useless since %r5 is already a boolean value.
It can thus be further simplified to:
setne.1 %r2 <- %arg1, $0
setne.1 %r4 <- %arg2, $0
or-bool.1 %r5 <- %r2, %r4
setne.1 %r9 <- %arg3, $0
or-bool.1 %r10 <- %r5, %r9
Change this by removing such comparisons if the operand is
already a boolean (its size is 1).
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
simplify.c | 3 ++-
validation/optim/bool-context-fp.c | 6 ++----
validation/optim/bool-simplify2.c | 11 +++++++++++
3 files changed, 15 insertions(+), 5 deletions(-)
create mode 100644 validation/optim/bool-simplify2.c
diff --git a/simplify.c b/simplify.c
index 09d7ae056..30bbc9b99 100644
--- a/simplify.c
+++ b/simplify.c
@@ -462,7 +462,8 @@ static int simplify_seteq_setne(struct instruction *insn, long long value)
return REPEAT_CSE;
default:
- break;
+ if (!inverse && def->size == 1)
+ return replace_with_pseudo(insn, old);
}
return 0;
}
diff --git a/validation/optim/bool-context-fp.c b/validation/optim/bool-context-fp.c
index 6b3e8d181..2f15fe94d 100644
--- a/validation/optim/bool-context-fp.c
+++ b/validation/optim/bool-context-fp.c
@@ -54,8 +54,7 @@ bfior:
fcmpune.1 %r20 <- %arg1, %r19
fcmpune.1 %r23 <- %arg2, %r19
or-bool.1 %r24 <- %r23, %r20
- setne.1 %r26 <- %r24, $0
- ret.1 %r26
+ ret.1 %r24
ifior:
@@ -76,8 +75,7 @@ bfand:
fcmpune.1 %r39 <- %arg1, %r38
fcmpune.1 %r42 <- %arg2, %r38
and-bool.1 %r43 <- %r42, %r39
- setne.1 %r45 <- %r43, $0
- ret.1 %r45
+ ret.1 %r43
ifand:
diff --git a/validation/optim/bool-simplify2.c b/validation/optim/bool-simplify2.c
new file mode 100644
index 000000000..caa5af053
--- /dev/null
+++ b/validation/optim/bool-simplify2.c
@@ -0,0 +1,11 @@
+static int foo(int a, int b, int c)
+{
+ return a || b || c;
+}
+
+/*
+ * check-name: bool-simplify2
+ * check-command: test-linearize $file
+ * check-output-ignore
+ * check-output-pattern-3-times: setne\\.
+ */
--
2.12.0
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