Auto merge of #73977 - Manishearth:rollup-2x4s7c6, r=Manishearth

Rollup of 8 pull requests

Successful merges:

 - #73454 (Move contributing.md to rustc-dev-guide and point at getting started)
 - #73724 (Use WASM's saturating casts if they are available)
 - #73726 (resolve: disallow labelled breaks/continues through closures/async blocks)
 - #73753 (Use 'tcx for references to AccessLevels wherever possible.)
 - #73781 (Update psm version)
 - #73952 (Add option for local docker testing.)
 - #73957 (disable BTree min_max test in Miri for now)
 - #73975 (Document rustc_ast::ast::Pat)

Failed merges:

r? @ghost

2 files changed, 10 insertions, 3 deletions

diff --git a/src/librustc_codegen_ssa/mir/rvalue.rs b/src/librustc_codegen_ssa/mir/rvalue.rs
index 57f72b1065d..4b2be7b5321 100644
--- a/src/librustc_codegen_ssa/mir/rvalue.rs
+++ b/src/librustc_codegen_ssa/mir/rvalue.rs
@@ -774,12 +774,17 @@ fn cast_float_to_int<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     float_ty: Bx::Type,
     int_ty: Bx::Type,
 ) -> Bx::Value {
-    let fptosui_result = if signed { bx.fptosi(x, int_ty) } else { bx.fptoui(x, int_ty) };
-
     if let Some(false) = bx.cx().sess().opts.debugging_opts.saturating_float_casts {
-        return fptosui_result;
+        return if signed { bx.fptosi(x, int_ty) } else { bx.fptoui(x, int_ty) };
+    }
+
+    let try_sat_result = if signed { bx.fptosi_sat(x, int_ty) } else { bx.fptoui_sat(x, int_ty) };
+    if let Some(try_sat_result) = try_sat_result {
+        return try_sat_result;
     }
 
+    let fptosui_result = if signed { bx.fptosi(x, int_ty) } else { bx.fptoui(x, int_ty) };
+
     let int_width = bx.cx().int_width(int_ty);
     let float_width = bx.cx().float_width(float_ty);
     // LLVM's fpto[su]i returns undef when the input x is infinite, NaN, or does not fit into the
diff --git a/src/librustc_codegen_ssa/traits/builder.rs b/src/librustc_codegen_ssa/traits/builder.rs
index 994d8e0395d..65eb70e173e 100644
--- a/src/librustc_codegen_ssa/traits/builder.rs
+++ b/src/librustc_codegen_ssa/traits/builder.rs
@@ -158,6 +158,8 @@ pub trait BuilderMethods<'a, 'tcx>:
 
     fn trunc(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;
     fn sext(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;
+    fn fptoui_sat(&mut self, val: Self::Value, dest_ty: Self::Type) -> Option<Self::Value>;
+    fn fptosi_sat(&mut self, val: Self::Value, dest_ty: Self::Type) -> Option<Self::Value>;
     fn fptoui(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;
     fn fptosi(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;
     fn uitofp(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;