@@ -440,9 +440,7 @@ void rewrite_load_instruction(struct instruction *insn, struct instruction_list
{
struct pseudo_list *dominators;
struct instruction *dom;
- pseudo_t new, phi;
-
- dominators = add_load_dominators(insn, doms, ident);
+ pseudo_t new;
/*
* Check for somewhat common case of duplicate
@@ -456,17 +454,18 @@ void rewrite_load_instruction(struct instruction *insn, struct instruction_list
} END_FOR_EACH_PTR(dom);
/*
- * All the same pseudo - mark the phi-nodes unused
- * and convert the load into a LNOP and replace the
- * pseudo.
+ * All the same pseudo - convert the load into a pseudo.
*/
- FOR_EACH_PTR(dominators, phi) {
- kill_instruction(phi->def);
- } END_FOR_EACH_PTR(phi);
convert_load_instruction(insn, new);
return;
complex_phi:
+ /*
+ * Not identical pseudos - create a phisrc for each
+ * dominators and convert the load into a phi-node.
+ */
+ dominators = add_load_dominators(insn, doms, ident);
+
/* We leave symbol pseudos with a bogus usage list here */
if (insn->src->type != PSEUDO_SYM)
kill_use(&insn->src);
@@ -39,11 +39,11 @@ static int fdo(void)
ffor:
.L0:
<entry-point>
- phisrc.32 %phi5(i) <- $0
+ phisrc.32 %phi3(i) <- $0
br .L4
.L4:
- phi.32 %r1(i) <- %phi5(i), %phi6(i)
+ phi.32 %r1(i) <- %phi3(i), %phi4(i)
setlt.32 %r2 <- %r1(i), $10
cbr %r2, .L1, .L3
@@ -58,7 +58,7 @@ ffor:
.L2:
add.32 %r7 <- %r1(i), $1
- phisrc.32 %phi6(i) <- %r7
+ phisrc.32 %phi4(i) <- %r7
br .L4
.L3:
@@ -73,11 +73,11 @@ ffor:
fwhile:
.L8:
<entry-point>
- phisrc.32 %phi11(i) <- $0
+ phisrc.32 %phi7(i) <- $0
br .L12
.L12:
- phi.32 %r8(i) <- %phi11(i), %phi12(i)
+ phi.32 %r8(i) <- %phi7(i), %phi8(i)
setlt.32 %r9 <- %r8(i), $10
cbr %r9, .L9, .L11
@@ -87,51 +87,51 @@ fwhile:
cbr %r11, .L14, .L13
.L13:
- phisrc.32 %phi7(return) <- $0
+ phisrc.32 %phi5(return) <- $0
br .L15
.L14:
add.32 %r14 <- %r8(i), $1
- phisrc.32 %phi12(i) <- %r14
+ phisrc.32 %phi8(i) <- %r14
br .L12
.L11:
- phisrc.32 %phi8(return) <- $1
+ phisrc.32 %phi6(return) <- $1
br .L15
.L15:
- phi.32 %r12 <- %phi7(return), %phi8(return)
+ phi.32 %r12 <- %phi5(return), %phi6(return)
ret.32 %r12
fdo:
.L16:
<entry-point>
- phisrc.32 %phi16(i) <- $0
+ phisrc.32 %phi11(i) <- $0
br .L17
.L17:
- phi.32 %r15(i) <- %phi16(i), %phi17(i)
+ phi.32 %r15(i) <- %phi11(i), %phi12(i)
push.32 %r15(i)
call.32 %r16 <- p
cbr %r16, .L18, .L20
.L20:
- phisrc.32 %phi13(return) <- $0
+ phisrc.32 %phi9(return) <- $0
br .L22
.L18:
add.32 %r19 <- %r15(i), $1
setlt.32 %r20 <- %r15(i), $10
- phisrc.32 %phi17(i) <- %r19
+ phisrc.32 %phi12(i) <- %r19
cbr %r20, .L17, .L19
.L19:
- phisrc.32 %phi14(return) <- $1
+ phisrc.32 %phi10(return) <- $1
br .L22
.L22:
- phi.32 %r17 <- %phi13(return), %phi14(return)
+ phi.32 %r17 <- %phi9(return), %phi10(return)
ret.32 %r17
In rewrite_load_instruction(), it's tested if the dominators are in fact all the same and if they are, as there is then no need for a phi-node, the newly created OP_PHISRCs are killed and the unique dominator is used in place of the phi-node. But in this case, it's a waste to have created the OP_PHISRCs as they are destroyed just after being created. Fix this by basically switching the order 'creating phi sources' and 'checking for uniqueness'. If the dominators are found to be all the same then use this unique dominator as the loaded value and no OP_PHISRC need to be created. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> --- flow.c | 17 ++++++++--------- validation/loop-linearization.c | 30 +++++++++++++++--------------- 2 files changed, 23 insertions(+), 24 deletions(-)