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authorPrashant-Shekhar-Rao <139104389+Prashant-Shekhar-Rao@users.noreply.github.com>2023-09-07 19:18:37 +0530
committerTshepang Mbambo <tshepang@gmail.com>2023-09-08 12:59:13 +0200
commite2cc9c817763b1ea4fe83bbc6a33cce642fd7633 (patch)
tree3b8d2d1a52a4ad4af202eb259d59a9fe4185868b /src/doc/rustc-dev-guide
parent88b4ea1932ba9abe87727eaf920b970885e36517 (diff)
downloadrust-e2cc9c817763b1ea4fe83bbc6a33cce642fd7633.tar.gz
rust-e2cc9c817763b1ea4fe83bbc6a33cce642fd7633.zip
Updated index.md to add a command which can show unoptimized MIR
The current playground link used in the page of MIR shows a optimized version of MIR which is missing some statements such as StorageLive . Updated to use a local command which shows unoptimized MIR that would be more useful for pedagogical purposes.
Diffstat (limited to 'src/doc/rustc-dev-guide')
-rw-r--r--src/doc/rustc-dev-guide/src/mir/index.md6
1 files changed, 6 insertions, 0 deletions
diff --git a/src/doc/rustc-dev-guide/src/mir/index.md b/src/doc/rustc-dev-guide/src/mir/index.md
index dc0be167b01..b90c5ad83b7 100644
--- a/src/doc/rustc-dev-guide/src/mir/index.md
+++ b/src/doc/rustc-dev-guide/src/mir/index.md
@@ -62,6 +62,12 @@ show you the MIR for your program. Try putting this program into play
 button on the top:
 
 [sample-play]: https://play.rust-lang.org/?gist=30074856e62e74e91f06abd19bd72ece&version=stable
+MIR shown by above link is optimized.
+Some statements like `StorageLive` are removed in optimization.
+This happens because compiler notices the value is never acessed in the code.
+We can use `rustc [filename].rs -Z mir-opt-level=0 --emit mir` to view unoptimized MIR.
+This requires the nightly toolchain.
+
 
 ```rust
 fn main() {