Dereference immutable borrows in GVN.

9 files changed, 71 insertions, 47 deletions

diff --git a/tests/coverage/issue-83601.cov-map b/tests/coverage/issue-83601.cov-map
index f2447e3c92c..ddb4407881a 100644
--- a/tests/coverage/issue-83601.cov-map
+++ b/tests/coverage/issue-83601.cov-map
@@ -1,12 +1,12 @@
 Function name: issue_83601::main
-Raw bytes (21): 0x[01, 01, 01, 05, 09, 03, 01, 06, 01, 02, 1c, 05, 03, 09, 01, 1c, 02, 02, 05, 03, 02]
+Raw bytes (21): 0x[01, 01, 01, 05, 00, 03, 01, 06, 01, 02, 1c, 05, 03, 09, 01, 1c, 02, 02, 05, 03, 02]
 Number of files: 1
 - file 0 => global file 1
 Number of expressions: 1
-- expression 0 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 0 operands: lhs = Counter(1), rhs = Zero
 Number of file 0 mappings: 3
 - Code(Counter(0)) at (prev + 6, 1) to (start + 2, 28)
 - Code(Counter(1)) at (prev + 3, 9) to (start + 1, 28)
 - Code(Expression(0, Sub)) at (prev + 2, 5) to (start + 3, 2)
-    = (c1 - c2)
+    = (c1 - Zero)
 
diff --git a/tests/coverage/issue-84561.cov-map b/tests/coverage/issue-84561.cov-map
index a81884ea942..ab66a2fffce 100644
--- a/tests/coverage/issue-84561.cov-map
+++ b/tests/coverage/issue-84561.cov-map
@@ -77,22 +77,22 @@ Number of file 0 mappings: 1
 - Code(Counter(0)) at (prev + 167, 9) to (start + 2, 10)
 
 Function name: issue_84561::test3
-Raw bytes (436): 0x[01, 01, 41, 05, 09, 0d, 00, 15, 19, 12, 00, 15, 19, 21, 00, 1e, 00, 21, 00, 31, 00, 3d, 41, 2e, 45, 3d, 41, 42, 49, 45, 00, 3f, 51, 42, 49, 45, 00, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 92, 01, 55, 51, 00, 8f, 01, 5d, 92, 01, 55, 51, 00, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 82, 01, 65, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 00, fe, 01, 82, 02, 00, 69, 6d, 69, 6d, 82, 02, 00, 69, 6d, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, ee, 01, 00, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 33, 01, 08, 01, 03, 1c, 05, 04, 09, 01, 1c, 02, 02, 05, 04, 1f, 0d, 05, 05, 00, 1f, 06, 01, 05, 00, 1f, 15, 01, 09, 01, 1c, 12, 02, 05, 00, 1f, 0e, 01, 05, 00, 0f, 00, 00, 20, 00, 30, 21, 01, 05, 03, 0f, 00, 03, 20, 00, 30, 00, 00, 33, 00, 41, 00, 00, 4b, 00, 5a, 1e, 01, 05, 00, 0f, 00, 05, 09, 03, 10, 00, 05, 0d, 00, 1b, 00, 02, 0d, 00, 1c, 1a, 04, 09, 05, 06, 31, 06, 05, 03, 06, 22, 04, 05, 03, 06, 3d, 04, 09, 04, 06, 2e, 05, 08, 00, 0f, 45, 01, 09, 03, 0a, 2a, 05, 09, 03, 0a, 3f, 05, 08, 00, 0f, 51, 01, 09, 00, 13, 00, 03, 0d, 00, 1d, 3a, 03, 09, 00, 13, 00, 03, 0d, 00, 1d, 87, 01, 03, 05, 00, 0f, 8f, 01, 01, 0c, 00, 13, 5d, 01, 0d, 00, 13, 8a, 01, 02, 0d, 00, 13, 82, 01, 04, 05, 02, 13, 65, 03, 0d, 00, 13, 7e, 02, 0d, 00, 13, f3, 01, 03, 05, 00, 0f, 69, 01, 0c, 00, 13, 6d, 01, 0d, 03, 0e, 75, 04, 0d, 00, 13, fb, 01, 02, 0d, 00, 17, 82, 02, 01, 14, 00, 1b, 00, 01, 15, 00, 1b, fe, 01, 02, 15, 00, 1b, f6, 01, 04, 0d, 00, 13, 7d, 03, 09, 00, 19, ee, 01, 02, 05, 00, 0f, ea, 01, 03, 09, 00, 22, 00, 02, 05, 00, 0f, 00, 03, 09, 00, 2c, 00, 02, 01, 00, 02]
+Raw bytes (436): 0x[01, 01, 41, 05, 00, 0d, 00, 15, 00, 12, 00, 15, 00, 21, 00, 1e, 00, 21, 00, 31, 00, 3d, 00, 2e, 45, 3d, 00, 42, 49, 45, 00, 3f, 51, 42, 49, 45, 00, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 92, 01, 55, 51, 00, 8f, 01, 5d, 92, 01, 55, 51, 00, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 82, 01, 65, 87, 01, 61, 5d, 8a, 01, 8f, 01, 5d, 92, 01, 55, 51, 00, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 00, fe, 01, 82, 02, 00, 69, 6d, 69, 6d, 82, 02, 00, 69, 6d, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, ee, 01, 00, f3, 01, 7d, 75, f6, 01, fb, 01, 79, 00, fe, 01, 82, 02, 00, 69, 6d, 33, 01, 08, 01, 03, 1c, 05, 04, 09, 01, 1c, 02, 02, 05, 04, 1f, 0d, 05, 05, 00, 1f, 06, 01, 05, 00, 1f, 15, 01, 09, 01, 1c, 12, 02, 05, 00, 1f, 0e, 01, 05, 00, 0f, 00, 00, 20, 00, 30, 21, 01, 05, 03, 0f, 00, 03, 20, 00, 30, 00, 00, 33, 00, 41, 00, 00, 4b, 00, 5a, 1e, 01, 05, 00, 0f, 00, 05, 09, 03, 10, 00, 05, 0d, 00, 1b, 00, 02, 0d, 00, 1c, 1a, 04, 09, 05, 06, 31, 06, 05, 03, 06, 22, 04, 05, 03, 06, 3d, 04, 09, 04, 06, 2e, 05, 08, 00, 0f, 45, 01, 09, 03, 0a, 2a, 05, 09, 03, 0a, 3f, 05, 08, 00, 0f, 51, 01, 09, 00, 13, 00, 03, 0d, 00, 1d, 3a, 03, 09, 00, 13, 00, 03, 0d, 00, 1d, 87, 01, 03, 05, 00, 0f, 8f, 01, 01, 0c, 00, 13, 5d, 01, 0d, 00, 13, 8a, 01, 02, 0d, 00, 13, 82, 01, 04, 05, 02, 13, 65, 03, 0d, 00, 13, 7e, 02, 0d, 00, 13, f3, 01, 03, 05, 00, 0f, 69, 01, 0c, 00, 13, 6d, 01, 0d, 03, 0e, 75, 04, 0d, 00, 13, fb, 01, 02, 0d, 00, 17, 82, 02, 01, 14, 00, 1b, 00, 01, 15, 00, 1b, fe, 01, 02, 15, 00, 1b, f6, 01, 04, 0d, 00, 13, 7d, 03, 09, 00, 19, ee, 01, 02, 05, 00, 0f, ea, 01, 03, 09, 00, 22, 00, 02, 05, 00, 0f, 00, 03, 09, 00, 2c, 00, 02, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
 Number of expressions: 65
-- expression 0 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 0 operands: lhs = Counter(1), rhs = Zero
 - expression 1 operands: lhs = Counter(3), rhs = Zero
-- expression 2 operands: lhs = Counter(5), rhs = Counter(6)
+- expression 2 operands: lhs = Counter(5), rhs = Zero
 - expression 3 operands: lhs = Expression(4, Sub), rhs = Zero
-- expression 4 operands: lhs = Counter(5), rhs = Counter(6)
+- expression 4 operands: lhs = Counter(5), rhs = Zero
 - expression 5 operands: lhs = Counter(8), rhs = Zero
 - expression 6 operands: lhs = Expression(7, Sub), rhs = Zero
 - expression 7 operands: lhs = Counter(8), rhs = Zero
 - expression 8 operands: lhs = Counter(12), rhs = Zero
-- expression 9 operands: lhs = Counter(15), rhs = Counter(16)
+- expression 9 operands: lhs = Counter(15), rhs = Zero
 - expression 10 operands: lhs = Expression(11, Sub), rhs = Counter(17)
-- expression 11 operands: lhs = Counter(15), rhs = Counter(16)
+- expression 11 operands: lhs = Counter(15), rhs = Zero
 - expression 12 operands: lhs = Expression(16, Sub), rhs = Counter(18)
 - expression 13 operands: lhs = Counter(17), rhs = Zero
 - expression 14 operands: lhs = Expression(15, Add), rhs = Counter(20)
@@ -150,15 +150,15 @@ Number of file 0 mappings: 51
 - Code(Counter(0)) at (prev + 8, 1) to (start + 3, 28)
 - Code(Counter(1)) at (prev + 4, 9) to (start + 1, 28)
 - Code(Expression(0, Sub)) at (prev + 2, 5) to (start + 4, 31)
-    = (c1 - c2)
+    = (c1 - Zero)
 - Code(Counter(3)) at (prev + 5, 5) to (start + 0, 31)
 - Code(Expression(1, Sub)) at (prev + 1, 5) to (start + 0, 31)
     = (c3 - Zero)
 - Code(Counter(5)) at (prev + 1, 9) to (start + 1, 28)
 - Code(Expression(4, Sub)) at (prev + 2, 5) to (start + 0, 31)
-    = (c5 - c6)
+    = (c5 - Zero)
 - Code(Expression(3, Sub)) at (prev + 1, 5) to (start + 0, 15)
-    = ((c5 - c6) - Zero)
+    = ((c5 - Zero) - Zero)
 - Code(Zero) at (prev + 0, 32) to (start + 0, 48)
 - Code(Counter(8)) at (prev + 1, 5) to (start + 3, 15)
 - Code(Zero) at (prev + 3, 32) to (start + 0, 48)
@@ -176,10 +176,10 @@ Number of file 0 mappings: 51
     = (c12 - Zero)
 - Code(Counter(15)) at (prev + 4, 9) to (start + 4, 6)
 - Code(Expression(11, Sub)) at (prev + 5, 8) to (start + 0, 15)
-    = (c15 - c16)
+    = (c15 - Zero)
 - Code(Counter(17)) at (prev + 1, 9) to (start + 3, 10)
 - Code(Expression(10, Sub)) at (prev + 5, 9) to (start + 3, 10)
-    = ((c15 - c16) - c17)
+    = ((c15 - Zero) - c17)
 - Code(Expression(15, Add)) at (prev + 5, 8) to (start + 0, 15)
     = ((c17 - Zero) + c18)
 - Code(Counter(20)) at (prev + 1, 9) to (start + 0, 19)
diff --git a/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff b/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff
index df3291bc1b5..e0e3136a498 100644
--- a/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff
+++ b/tests/mir-opt/gvn.borrowed.GVN.panic-abort.diff
@@ -18,7 +18,8 @@
       }
   
       bb2: {
-          _0 = opaque::<u32>((*_3)) -> [return: bb3, unwind unreachable];
+-         _0 = opaque::<u32>((*_3)) -> [return: bb3, unwind unreachable];
++         _0 = opaque::<u32>(_1) -> [return: bb3, unwind unreachable];
       }
   
       bb3: {
diff --git a/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff b/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff
index 8f670de61ee..e60e1b22c9a 100644
--- a/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff
+++ b/tests/mir-opt/gvn.borrowed.GVN.panic-unwind.diff
@@ -18,7 +18,8 @@
       }
   
       bb2: {
-          _0 = opaque::<u32>((*_3)) -> [return: bb3, unwind continue];
+-         _0 = opaque::<u32>((*_3)) -> [return: bb3, unwind continue];
++         _0 = opaque::<u32>(_1) -> [return: bb3, unwind continue];
       }
   
       bb3: {
diff --git a/tests/mir-opt/gvn.rs b/tests/mir-opt/gvn.rs
index f168d4fec89..8c2d4db642d 100644
--- a/tests/mir-opt/gvn.rs
+++ b/tests/mir-opt/gvn.rs
@@ -730,7 +730,7 @@ fn borrowed(x: u32) {
     // CHECK: bb1: {
     // CHECK-NEXT: _0 = opaque::<u32>(_1)
     // CHECK: bb2: {
-    // CHECK-NEXT: _0 = opaque::<u32>((*_3))
+    // CHECK-NEXT: _0 = opaque::<u32>(_1)
     mir!(
         {
             let a = x;
diff --git a/tests/mir-opt/gvn.slices.GVN.panic-abort.diff b/tests/mir-opt/gvn.slices.GVN.panic-abort.diff
index 2389d98b5b3..fb67e3d5994 100644
--- a/tests/mir-opt/gvn.slices.GVN.panic-abort.diff
+++ b/tests/mir-opt/gvn.slices.GVN.panic-abort.diff
@@ -111,8 +111,9 @@
           StorageLive(_7);
           StorageLive(_8);
 -         StorageLive(_9);
+-         StorageLive(_10);
++         nop;
 +         nop;
-          StorageLive(_10);
           StorageLive(_11);
           _11 = &(*_1);
           _10 = core::str::<impl str>::as_ptr(move _11) -> [return: bb3, unwind unreachable];
@@ -122,8 +123,9 @@
           StorageDead(_11);
           _9 = &_10;
 -         StorageLive(_12);
+-         StorageLive(_13);
++         nop;
 +         nop;
-          StorageLive(_13);
           StorageLive(_14);
 -         _14 = &(*_4);
 +         _14 = &(*_1);
@@ -148,11 +150,12 @@
           StorageLive(_17);
           StorageLive(_18);
 -         _18 = (*_15);
-+         _18 = (*_9);
++         _18 = _10;
           StorageLive(_19);
 -         _19 = (*_16);
-+         _19 = (*_12);
-          _17 = Eq(move _18, move _19);
+-         _17 = Eq(move _18, move _19);
++         _19 = _13;
++         _17 = Eq(_10, _13);
           switchInt(move _17) -> [0: bb6, otherwise: bb5];
       }
   
@@ -163,8 +166,10 @@
           StorageDead(_17);
           StorageDead(_16);
           StorageDead(_15);
-          StorageDead(_13);
-          StorageDead(_10);
+-         StorageDead(_13);
+-         StorageDead(_10);
++         nop;
++         nop;
           StorageDead(_8);
           StorageDead(_7);
 -         StorageLive(_29);
@@ -213,8 +218,9 @@
           StorageLive(_33);
           StorageLive(_34);
 -         StorageLive(_35);
+-         StorageLive(_36);
++         nop;
 +         nop;
-          StorageLive(_36);
           StorageLive(_37);
           _37 = &(*_1);
           _36 = core::str::<impl str>::as_ptr(move _37) -> [return: bb8, unwind unreachable];
@@ -224,8 +230,9 @@
           StorageDead(_37);
           _35 = &_36;
 -         StorageLive(_38);
+-         StorageLive(_39);
++         nop;
 +         nop;
-          StorageLive(_39);
           StorageLive(_40);
           _40 = &(*_29);
           _39 = core::slice::<impl [u8]>::as_ptr(move _40) -> [return: bb9, unwind unreachable];
@@ -249,11 +256,12 @@
           StorageLive(_43);
           StorageLive(_44);
 -         _44 = (*_41);
-+         _44 = (*_35);
++         _44 = _36;
           StorageLive(_45);
 -         _45 = (*_42);
-+         _45 = (*_38);
-          _43 = Eq(move _44, move _45);
+-         _43 = Eq(move _44, move _45);
++         _45 = _39;
++         _43 = Eq(_36, _39);
           switchInt(move _43) -> [0: bb11, otherwise: bb10];
       }
   
@@ -264,8 +272,10 @@
           StorageDead(_43);
           StorageDead(_42);
           StorageDead(_41);
-          StorageDead(_39);
-          StorageDead(_36);
+-         StorageDead(_39);
+-         StorageDead(_36);
++         nop;
++         nop;
           StorageDead(_34);
           StorageDead(_33);
           _0 = const ();
diff --git a/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff b/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff
index 50715d748e7..ae3013b011e 100644
--- a/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff
+++ b/tests/mir-opt/gvn.slices.GVN.panic-unwind.diff
@@ -111,8 +111,9 @@
           StorageLive(_7);
           StorageLive(_8);
 -         StorageLive(_9);
+-         StorageLive(_10);
++         nop;
 +         nop;
-          StorageLive(_10);
           StorageLive(_11);
           _11 = &(*_1);
           _10 = core::str::<impl str>::as_ptr(move _11) -> [return: bb3, unwind continue];
@@ -122,8 +123,9 @@
           StorageDead(_11);
           _9 = &_10;
 -         StorageLive(_12);
+-         StorageLive(_13);
++         nop;
 +         nop;
-          StorageLive(_13);
           StorageLive(_14);
 -         _14 = &(*_4);
 +         _14 = &(*_1);
@@ -148,11 +150,12 @@
           StorageLive(_17);
           StorageLive(_18);
 -         _18 = (*_15);
-+         _18 = (*_9);
++         _18 = _10;
           StorageLive(_19);
 -         _19 = (*_16);
-+         _19 = (*_12);
-          _17 = Eq(move _18, move _19);
+-         _17 = Eq(move _18, move _19);
++         _19 = _13;
++         _17 = Eq(_10, _13);
           switchInt(move _17) -> [0: bb6, otherwise: bb5];
       }
   
@@ -163,8 +166,10 @@
           StorageDead(_17);
           StorageDead(_16);
           StorageDead(_15);
-          StorageDead(_13);
-          StorageDead(_10);
+-         StorageDead(_13);
+-         StorageDead(_10);
++         nop;
++         nop;
           StorageDead(_8);
           StorageDead(_7);
 -         StorageLive(_29);
@@ -213,8 +218,9 @@
           StorageLive(_33);
           StorageLive(_34);
 -         StorageLive(_35);
+-         StorageLive(_36);
++         nop;
 +         nop;
-          StorageLive(_36);
           StorageLive(_37);
           _37 = &(*_1);
           _36 = core::str::<impl str>::as_ptr(move _37) -> [return: bb8, unwind continue];
@@ -224,8 +230,9 @@
           StorageDead(_37);
           _35 = &_36;
 -         StorageLive(_38);
+-         StorageLive(_39);
++         nop;
 +         nop;
-          StorageLive(_39);
           StorageLive(_40);
           _40 = &(*_29);
           _39 = core::slice::<impl [u8]>::as_ptr(move _40) -> [return: bb9, unwind continue];
@@ -249,11 +256,12 @@
           StorageLive(_43);
           StorageLive(_44);
 -         _44 = (*_41);
-+         _44 = (*_35);
++         _44 = _36;
           StorageLive(_45);
 -         _45 = (*_42);
-+         _45 = (*_38);
-          _43 = Eq(move _44, move _45);
+-         _43 = Eq(move _44, move _45);
++         _45 = _39;
++         _43 = Eq(_36, _39);
           switchInt(move _43) -> [0: bb11, otherwise: bb10];
       }
   
@@ -264,8 +272,10 @@
           StorageDead(_43);
           StorageDead(_42);
           StorageDead(_41);
-          StorageDead(_39);
-          StorageDead(_36);
+-         StorageDead(_39);
+-         StorageDead(_36);
++         nop;
++         nop;
           StorageDead(_34);
           StorageDead(_33);
           _0 = const ();
diff --git a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff
index c5ee0d9c44d..626367766d7 100644
--- a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff
+++ b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-abort.diff
@@ -17,7 +17,8 @@
           StorageLive(_3);
           _5 = const f::promoted[0];
           _3 = &(*_5);
-          _2 = ((*_3).1: E);
+-         _2 = ((*_3).1: E);
++         _2 = ((*_5).1: E);
           StorageLive(_1);
 -         _1 = ((_2 as A).1: u32);
 +         _1 = const 0_u32;
diff --git a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff
index c5ee0d9c44d..626367766d7 100644
--- a/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff
+++ b/tests/mir-opt/gvn_uninhabited.f.GVN.panic-unwind.diff
@@ -17,7 +17,8 @@
           StorageLive(_3);
           _5 = const f::promoted[0];
           _3 = &(*_5);
-          _2 = ((*_3).1: E);
+-         _2 = ((*_3).1: E);
++         _2 = ((*_5).1: E);
           StorageLive(_1);
 -         _1 = ((_2 as A).1: u32);
 +         _1 = const 0_u32;