nir/validate: Require unused bits of nir_const_value to be zero

Reviewed-by: Karol Herbst <[email protected]>

1 files changed, 35 insertions, 0 deletions

diff --git a/src/compiler/nir/nir_validate.c b/src/compiler/nir/nir_validate.c
index 9a950218208..7746c391abc 100644
--- a/src/compiler/nir/nir_validate.c
+++ b/src/compiler/nir/nir_validate.c
@@ -620,9 +620,44 @@ validate_call_instr(nir_call_instr *instr, validate_state *state)
 }
 
 static void
+validate_const_value(nir_const_value *val, unsigned bit_size,
+                     validate_state *state)
+{
+   /* In order for block copies to work properly for things like instruction
+    * comparisons and [de]serialization, we require the unused bits of the
+    * nir_const_value to be zero.
+    */
+   nir_const_value cmp_val;
+   memset(&cmp_val, 0, sizeof(cmp_val));
+   switch (bit_size) {
+   case 1:
+      cmp_val.b = val->b;
+      break;
+   case 8:
+      cmp_val.u8 = val->u8;
+      break;
+   case 16:
+      cmp_val.u16 = val->u16;
+      break;
+   case 32:
+      cmp_val.u32 = val->u32;
+      break;
+   case 64:
+      cmp_val.u64 = val->u64;
+      break;
+   default:
+      validate_assert(state, !"Invalid load_const bit size");
+   }
+   validate_assert(state, memcmp(val, &cmp_val, sizeof(cmp_val)) == 0);
+}
+
+static void
 validate_load_const_instr(nir_load_const_instr *instr, validate_state *state)
 {
    validate_ssa_def(&instr->def, state);
+
+   for (unsigned i = 0; i < instr->def.num_components; i++)
+      validate_const_value(&instr->value[i], instr->def.bit_size, state);
 }
 
 static void