Adds support for the EVM version "Paris".

Deprecates `block.difficulty` and disallow `difficulty()` in inline assembly for EVM versions >= paris.
The change is due to the renaming introduced by EIP-4399 (see: https://eips.ethereum.org/EIPS/eip-4399).
Introduces `block.prevrandao` in Solidity and `prevrandao()` in inline assembly for EVM versions >= paris.

Co-authored-by: Alex Beregszaszi <alex@rtfs.hu>
Co-authored-by: Daniel <daniel@ekpyron.org>
Co-authored-by: matheusaaguiar <95899911+matheusaaguiar@users.noreply.github.com>
Co-authored-by: Nikola Matić <nikola.matic@ethereum.org>

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_allowed.sol

@@ -73,7 +73,7 @@ contract C {
             pop(coinbase())
             pop(timestamp())
             pop(number())
-            pop(difficulty())
+            pop(prevrandao())
             pop(gaslimit())
 
             // NOTE: msize() is allowed only with optimizer disabled
@@ -83,7 +83,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=london
+// EVMVersion: >=paris
 // ----
 // Warning 5740: (89-1716): Unreachable code.
 // Warning 5740: (1729-1741): Unreachable code.

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_allowed_london.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public {
+        assembly {
+            pop(difficulty())
+        }
+    }
+}
+// ====
+// EVMVersion: <=london
+// ----
+// Warning 2018: (17-103): Function state mutability can be restricted to view

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_allowed_pure.sol

@@ -73,7 +73,6 @@ contract C {
             //pop(coinbase())
             //pop(timestamp())
             //pop(number())
-            //pop(difficulty())
             //pop(gaslimit())
 
             // NOTE: msize() is allowed only with optimizer disabled

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_allowed_view.sol

@@ -73,7 +73,7 @@ contract C {
             pop(coinbase())
             pop(timestamp())
             pop(number())
-            pop(difficulty())
+            pop(prevrandao())
             pop(gaslimit())
 
             // NOTE: msize() is allowed only with optimizer disabled
@@ -83,7 +83,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=london
+// EVMVersion: >=paris
 // ----
 // Warning 5740: (94-1733): Unreachable code.
 // Warning 5740: (1746-1758): Unreachable code.

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_allowed_view_london.sol

@@ -0,0 +1,10 @@
+contract C {
+    function f() public view {
+        assembly {
+            pop(difficulty())
+        }
+    }
+}
+// ====
+// EVMVersion: <=london
+// ----

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure.sol

@@ -6,33 +6,26 @@ contract C {
             pop(gas())
             pop(address())
             pop(balance(0))
-            pop(selfbalance())
             pop(caller())
             pop(callvalue())
             pop(extcodesize(0))
             extcodecopy(0, 1, 2, 3)
-            pop(extcodehash(0))
             pop(create(0, 1, 2))
-            pop(create2(0, 1, 2, 3))
             pop(call(0, 1, 2, 3, 4, 5, 6))
             pop(callcode(0, 1, 2, 3, 4, 5, 6))
             pop(delegatecall(0, 1, 2, 3, 4, 5))
-            pop(staticcall(0, 1, 2, 3, 4, 5))
             selfdestruct(0)
             log0(0, 1)
             log1(0, 1, 2)
             log2(0, 1, 2, 3)
             log3(0, 1, 2, 3, 4)
             log4(0, 1, 2, 3, 4, 5)
-            pop(chainid())
-            pop(basefee())
             pop(origin())
             pop(gasprice())
             pop(blockhash(0))
             pop(coinbase())
             pop(timestamp())
             pop(number())
-            pop(difficulty())
             pop(gaslimit())
 
             // These two are disallowed too but the error suppresses other errors.
@@ -41,40 +34,31 @@ contract C {
         }
     }
 }
-// ====
-// EVMVersion: >=london
 // ----
-// Warning 5740: (672-1083): Unreachable code.
+// Warning 5740: (526-853): Unreachable code.
 // TypeError 2527: (79-87): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
 // TypeError 8961: (101-113): Function cannot be declared as pure because this expression (potentially) modifies the state.
 // TypeError 2527: (130-135): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
 // TypeError 2527: (153-162): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
 // TypeError 2527: (180-190): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (208-221): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (239-247): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (265-276): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (294-308): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (322-345): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (362-376): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 8961: (394-409): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (427-446): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (464-489): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (507-536): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (554-584): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 2527: (602-630): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 8961: (644-659): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (672-682): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (695-708): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (721-737): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (750-769): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 8961: (782-804): Function cannot be declared as pure because this expression (potentially) modifies the state.
-// TypeError 2527: (821-830): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (848-857): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (875-883): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (901-911): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (929-941): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (959-969): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (987-998): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (1016-1024): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (1042-1054): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
-// TypeError 2527: (1072-1082): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (208-216): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (234-245): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (263-277): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (291-314): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 8961: (331-346): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (364-389): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (407-436): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (454-484): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (498-513): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (526-536): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (549-562): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (575-591): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (604-623): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 8961: (636-658): Function cannot be declared as pure because this expression (potentially) modifies the state.
+// TypeError 2527: (675-683): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (701-711): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (729-741): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (759-769): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (787-798): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (816-824): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (842-852): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_byzantium.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(staticcall(0, 1, 2, 3, 4, 5))
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// TypeError 2527: (79-107): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_constantinople.sol

@@ -0,0 +1,13 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(extcodehash(0))
+            pop(create2(0, 1, 2, 3))
+        }
+    }
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// TypeError 2527: (79-93): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 8961: (111-130): Function cannot be declared as pure because this expression (potentially) modifies the state.

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_istanbul.sol

@@ -0,0 +1,13 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(selfbalance())
+            pop(chainid())
+        }
+    }
+}
+// ====
+// EVMVersion: >=istanbul
+// ----
+// TypeError 2527: (79-92): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".
+// TypeError 2527: (110-119): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_london.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(basefee())
+        }
+    }
+}
+// ====
+// EVMVersion: >=london
+// ----
+// TypeError 2527: (79-88): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_paris.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(prevrandao())
+        }
+    }
+}
+// ====
+// EVMVersion: >=paris
+// ----
+// TypeError 2527: (79-91): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".

test/libsolidity/syntaxTests/viewPureChecker/inline_assembly_instructions_disallowed_pure_pre_paris.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public pure {
+        assembly {
+            pop(difficulty())
+        }
+    }
+}
+// ====
+// EVMVersion: <=london
+// ----
+// TypeError 2527: (79-91): Function declared as pure, but this expression (potentially) reads from the environment or state and thus requires "view".