Auto merge of #29735 - Amanieu:asm_indirect_constraint, r=pnkfelix

This PR reverts #29543 and instead implements proper support for "=*m" and "+*m" indirect output operands. This provides a framework on top of which support for plain memory operands ("m", "=m" and "+m") can be implemented.

This also fixes the liveness analysis pass not handling read/write operands correctly.

1 files changed, 9 insertions, 3 deletions

diff --git a/src/libsyntax/ext/asm.rs b/src/libsyntax/ext/asm.rs
index d968858f634..b4f29f83726 100644
--- a/src/libsyntax/ext/asm.rs
+++ b/src/libsyntax/ext/asm.rs
@@ -125,7 +125,13 @@ pub fn expand_asm<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
                     };
 
                     let is_rw = output.is_some();
-                    outputs.push((output.unwrap_or(constraint), out, is_rw));
+                    let is_indirect = constraint.contains("*");
+                    outputs.push(ast::InlineAsmOutput {
+                        constraint: output.unwrap_or(constraint),
+                        expr: out,
+                        is_rw: is_rw,
+                        is_indirect: is_indirect,
+                    });
                 }
             }
             Inputs => {
@@ -139,9 +145,9 @@ pub fn expand_asm<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
 
                     let (constraint, _str_style) = panictry!(p.parse_str());
 
-                    if constraint.starts_with("=") && !constraint.contains("*") {
+                    if constraint.starts_with("=") {
                         cx.span_err(p.last_span, "input operand constraint contains '='");
-                    } else if constraint.starts_with("+") && !constraint.contains("*") {
+                    } else if constraint.starts_with("+") {
                         cx.span_err(p.last_span, "input operand constraint contains '+'");
                     }