diff --git a/src/back/msl.rs b/src/back/msl.rs
index 20b752bc9b..10336b7823 100644
--- a/src/back/msl.rs
+++ b/src/back/msl.rs
@@ -56,6 +56,7 @@ pub enum Error {
     MixedExecutionModels(crate::Token<crate::Function>),
     MissingBinding(crate::Token<crate::GlobalVariable>),
     MissingBindTarget(BindSource),
+    InvalidImageFlags(crate::ImageFlags),
     BadName(String),
 }
 
@@ -510,14 +511,19 @@ impl<W: Write> Writer<W> {
                         spirv::Dim::DimCube => "Cube",
                         _ => panic!("Unsupported dim {:?}", dim),
                     };
-                    let access = if flags.contains(crate::ImageFlags::READABLE | crate::ImageFlags::WRITABLE) {
-                        "read_write"
-                    } else if flags.contains(crate::ImageFlags::WRITABLE) {
-                        "write"
-                    } else {
-                        assert!(flags.contains(crate::ImageFlags::READABLE));
-                        //TODO: figure out when to use `read`
+                    let access = if flags.contains(crate::ImageFlags::SAMPLED) {
+                        if flags.intersects(crate::ImageFlags::CAN_STORE) {
+                            return Err(Error::InvalidImageFlags(flags));
+                        }
                         "sample"
+                    } else if flags.contains(crate::ImageFlags::CAN_LOAD | crate::ImageFlags::CAN_STORE) {
+                        "read_write"
+                    } else if flags.contains(crate::ImageFlags::CAN_STORE) {
+                        "write"
+                    } else if flags.contains(crate::ImageFlags::CAN_LOAD) {
+                        "read"
+                    } else {
+                        return Err(Error::InvalidImageFlags(flags));
                     };
                     write!(self.out, "typedef texture{}<{}, access::{}> {}", dim, base_name, access, name)?;
                 }
diff --git a/src/front/spirv.rs b/src/front/spirv.rs
index 020b63188d..45b768db84 100644
--- a/src/front/spirv.rs
+++ b/src/front/spirv.rs
@@ -1066,21 +1066,21 @@ impl<I: Iterator<Item = u32>> Parser<I> {
                         flags |= crate::ImageFlags::MULTISAMPLED;
                     }
                     let is_sampled = self.next()?;
+                    if is_sampled != 0 {
+                        flags |= crate::ImageFlags::SAMPLED;
+                    }
                     let _format = self.next()?;
-                    let access = if inst.wc > 9 {
+                    if inst.wc > 9 {
                         inst.expect(10)?;
-                        self.next()?
-                    } else if is_sampled == 1 {
-                        0 // read-only
-                    } else {
-                        2 // read-write
+                        let access = self.next()?;
+                        if access == 0 || access == 2 {
+                            flags |= crate::ImageFlags::CAN_LOAD;
+                        }
+                        if access == 1 || access == 2 {
+                            flags |= crate::ImageFlags::CAN_STORE;
+                        }
                     };
-                    if access == 0 || access == 2 {
-                        flags |= crate::ImageFlags::READABLE;
-                    }
-                    if access == 1 || access == 2 {
-                        flags |= crate::ImageFlags::WRITABLE;
-                    }
+
                     let decor = self.future_decor
                         .remove(&id)
                         .unwrap_or_default();
diff --git a/src/lib.rs b/src/lib.rs
index 70e28471c8..ad61a83594 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -60,8 +60,9 @@ bitflags::bitflags! {
     pub struct ImageFlags: u32 {
         const ARRAYED = 0x1;
         const MULTISAMPLED = 0x2;
-        const READABLE = 0x4;
-        const WRITABLE = 0x8;
+        const SAMPLED = 0x4;
+        const CAN_LOAD = 0x10;
+        const CAN_STORE = 0x20;
     }
 }