Some casts, the ones which doesn't change the size or the resulting
'machine type', are no-op.
Directly simplify away such casts.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
linearize.c | 8 ++++++++
validation/linear/cast-kinds.c | 15 +++++++++++++++
2 files changed, 23 insertions(+)
diff --git a/linearize.c b/linearize.c
index c6c377b2e..0258a82a5 100644
--- a/linearize.c
+++ b/linearize.c
@@ -1206,6 +1206,8 @@ static int get_cast_opcode(struct symbol *dst, struct symbol *src)
case MTYPE_FLOAT:
switch (stype) {
case MTYPE_FLOAT:
+ if (dst->bit_size == src->bit_size)
+ return OP_NOP;
return OP_FCVTF;
case MTYPE_UINT:
return OP_UCVTF;
@@ -1243,6 +1245,12 @@ static pseudo_t cast_pseudo(struct entrypoint *ep, pseudo_t src, struct symbol *
if (from->bit_size < 0 || to->bit_size < 0)
return VOID;
opcode = get_cast_opcode(to, from);
+ switch (opcode) {
+ case OP_NOP:
+ return src;
+ default:
+ break;
+ }
insn = alloc_typed_instruction(opcode, to);
result = alloc_pseudo(insn);
insn->target = result;
diff --git a/validation/linear/cast-kinds.c b/validation/linear/cast-kinds.c
index d8ac5d34f..5944610c6 100644
--- a/validation/linear/cast-kinds.c
+++ b/validation/linear/cast-kinds.c
@@ -50,6 +50,9 @@ static double long_2_double(long a) { return (double)a; }
static double ulong_2_double(ulong a) { return (double)a; }
static double float_2_double(float a) { return (double)a; }
+static float float_2_float(float a) { return a; }
+static double double_2_double(double a) { return a; }
+
/*
* check-name: cast-kinds
* check-command: test-linearize -m64 $file
@@ -387,5 +390,17 @@ float_2_double:
ret.64 %r143
+float_2_float:
+.L96:
+ <entry-point>
+ ret.32 %arg1
+
+
+double_2_double:
+.L98:
+ <entry-point>
+ ret.64 %arg1
+
+
* check-output-end
*/
--
2.17.1
--
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