Don't renumber entities in the parser.

This makes it easier to debug testcases:
 - the entity numbers in a .cton file match the entity numbers used
   within Cretonne.
 - serializing and deserializing doesn't cause indices to change.

One disadvantage is that if a .cton file uses sparse entity numbers,
deserializing to the in-memory form doesn't compact it. However, the
text format is not intended to be performance-critical, so this isn't
expected to be a big burden.

cranelift/filetests/parser/branch.cton

@@ -95,19 +95,18 @@ ebb40:
     trap user4
 }
 ; sameln: function %jumptable(i32) native {
-; nextln:     jt0 = jump_table 0
-; nextln:     jt1 = jump_table 0, 0, ebb0, ebb3, ebb1, ebb2
-; nextln: 
-; nextln: ebb0($v3: i32):
-; nextln:     br_table $v3, jt1
+; check:      jt2 = jump_table 0, 0, ebb10, ebb40, ebb20, ebb30
+; check:      jt200 = jump_table 0
+; check:  ebb10($v3: i32):
+; nextln:     br_table $v3, jt2
 ; nextln:     trap user1
 ; nextln: 
-; nextln: ebb1:
+; nextln: ebb20:
 ; nextln:     trap user2
 ; nextln: 
-; nextln: ebb2:
+; nextln: ebb30:
 ; nextln:     trap user3
 ; nextln: 
-; nextln: ebb3:
+; nextln: ebb40:
 ; nextln:     trap user4
 ; nextln: }

cranelift/filetests/parser/call.cton

@@ -6,7 +6,7 @@ ebb1:
     return
 }
 ; sameln: function %mini() native {
-; nextln: ebb0:
+; nextln: ebb1:
 ; nextln:     return
 ; nextln: }
 
@@ -17,7 +17,7 @@ ebb1:
     return v1, v2
 }
 ; sameln: function %r1() -> i32, f32 spiderwasm {
-; nextln: ebb0:
+; nextln: ebb1:
 ; nextln:     $v1 = iconst.i32 3
 ; nextln:     $v2 = f32const 0.0
 ; nextln:     return $v1, $v2
@@ -30,12 +30,12 @@ function %signatures() {
     fn8 = function %bar(i32) -> b1
 }
 ; sameln: function %signatures() native {
-; nextln:     $sig10 = () native
-; nextln:     $sig11 = (i32, f64) -> i32, b1 spiderwasm
-; nextln:     sig2 = (i32) -> b1 native
-; nextln:     $fn5 = $sig11 %foo
-; nextln:     $fn8 = sig2 %bar
-; nextln: }
+; check:      $sig10 = () native
+; check:      $sig11 = (i32, f64) -> i32, b1 spiderwasm
+; check:      sig12 = (i32) -> b1 native
+; check:      $fn5 = $sig11 %foo
+; check:      $fn8 = sig12 %bar
+; check:  }
 
 function %direct() {
     fn0 = function %none()

cranelift/filetests/parser/rewrite.cton

@@ -30,8 +30,8 @@ ebb100(v20: i32):
     jump ebb100(v1000)
 }
 ; sameln: function %use_value() native {
-; nextln: ebb0($v20: i32):
+; nextln: ebb100($v20: i32):
 ; nextln:     $v1000 = iadd_imm $v20, 5
 ; nextln:     $v200 = iadd $v20, $v1000
-; nextln:     jump ebb0($v1000)
+; nextln:     jump ebb100($v1000)
 ; nextln: }

cranelift/filetests/parser/tiny.cton

@@ -58,8 +58,8 @@ ebb0(v95: i32, v96: i32, v97: b1):
     v98 = selectif.i32 eq v97, v95, v96
 }
 ; sameln: function %selectif() native {
-; nextln: ebb0(v0: i32, v1: i32, v2: b1):
-; nextln: v3 = selectif.i32 eq v2, v0, v1
+; nextln: ebb0(v95: i32, v96: i32, v97: b1):
+; nextln: v98 = selectif.i32 eq v97, v95, v96
 ; nextln: }
 
 ; Lane indexes.
@@ -136,11 +136,11 @@ ebb0:
     stack_store v2, ss2
 }
 ; sameln: function %stack() native {
-; nextln:    $ss10 = spill_slot 8
-; nextln:    $ss2 = local 4
-; nextln:    $ss3 = incoming_arg 4, offset 8
-; nextln:    $ss4 = outgoing_arg 4
-; nextln:    $ss5 = emergency_slot 4
+; check:     $ss2 = local 4
+; check:     $ss3 = incoming_arg 4, offset 8
+; check:     $ss4 = outgoing_arg 4
+; check:     $ss5 = emergency_slot 4
+; check:     $ss10 = spill_slot 8
 
 ; check: ebb0:
 ; nextln: $v1 = stack_load.i32 $ss10