Merge pull request #14468 from ethereum/push0-rematerializer-default-sequence

Push0 rematerializer default sequence

Author: ekpyron

Changelog.md

@@ -6,6 +6,7 @@ Language Features:
 Compiler Features:
  * Parser: Remove the experimental error recovery mode (``--error-recovery`` / ``settings.parserErrorRecovery``).
  * Yul Optimizer: If ``PUSH0`` is supported, favor zero literals over storing zero values in variables.
+ * Yul Optimizer: Run the ``Rematerializer`` and ``UnusedPruner`` steps at the end of the default clean-up sequence.
 
 
 Bugfixes:

docs/internals/optimizer.rst

@@ -338,7 +338,7 @@ You can override this sequence and supply your own using the ``--yul-optimizatio
 
 .. code-block:: bash
 
-    solc --optimize --ir-optimized --yul-optimizations 'dhfoD[xarrscLMcCTU]uljmul:fDnTOc'
+    solc --optimize --ir-optimized --yul-optimizations 'dhfoD[xarrscLMcCTU]uljmul:fDnTOcmu'
 
 The order of steps is significant and affects the quality of the output.
 Moreover, applying a step may uncover new optimization opportunities for others that were already applied,

libsolidity/interface/OptimiserSettings.h

@@ -59,7 +59,7 @@ struct OptimiserSettings
 		"]"
 		"jmul[jul] VcTOcul jmul";      // Make source short and pretty
 
-	static char constexpr DefaultYulOptimiserCleanupSteps[] = "fDnTOc";
+	static char constexpr DefaultYulOptimiserCleanupSteps[] = "fDnTOcmu";
 
 	/// No optimisations at all - not recommended.
 	static OptimiserSettings none()

test/cmdlineTests/name_simplifier/output

@@ -101,7 +101,7 @@ object "C_59" {
                         mstore(add(memPtr_1, _3), "longstringlongstringlongstringlo")
                         mstore(add(memPtr_1, _9), "ngstringlongstringlongstringlong")
                         let _11 := 96
-                        mstore(add(memPtr_1, _11), "stringlongstringlongstringlongst")
+                        mstore(add(memPtr_1, 96), "stringlongstringlongstringlongst")
                         mstore(add(memPtr_1, 128), "ring")
                         let memPos := mload(_9)
                         mstore(memPos, _10)
@@ -113,8 +113,8 @@ object "C_59" {
                         {
                             mstore(add(add(memPos, i), _11), mload(add(add(memPtr_1, i), _3)))
                         }
-                        mstore(add(add(memPos, length), _11), 0)
-                        return(memPos, add(sub(add(memPos, and(add(length, 31), _8)), memPos), _11))
+                        mstore(add(add(memPos, length), 96), 0)
+                        return(memPos, add(sub(add(memPos, and(add(length, 31), _8)), memPos), 96))
                     }
                 }
                 revert(0, 0)

test/cmdlineTests/optimizer_array_sload/output

@@ -19,16 +19,16 @@ object "Arraysum_34" {
                 /// @src 0:80:429  "contract Arraysum {..."
                 mstore(64, memoryguard(0x80))
                 let _1 := 4
-                if iszero(lt(calldatasize(), _1))
+                if iszero(lt(calldatasize(), 4))
                 {
                     if eq(0x81d73423, shr(224, calldataload(0)))
                     {
                         if callvalue() { revert(0, 0) }
                         if slt(add(calldatasize(), not(3)), 0) { revert(0, 0) }
                         let var_sum := 0
                         /// @src 0:368:378  "uint i = 0"
-                        let var_i := /** @src 0:80:429  "contract Arraysum {..." */ var_sum
-                        let _2 := sload(var_sum)
+                        let var_i := /** @src 0:80:429  "contract Arraysum {..." */ 0
+                        let _2 := sload(0)
                         /// @src 0:364:423  "for(uint i = 0; i < values.length; i++)..."
                         for { }
                         /** @src 0:380:397  "i < values.length" */ lt(var_i, _2)