From 5c1e0f0cce5308cd67a4bf77062d90f1e065c51d Mon Sep 17 00:00:00 2001
From: belliash <belliash@codingworkshop.eu.org>
Date: Tue, 30 Apr 2019 23:59:02 +0200
Subject: [PATCH] Simplify the foreach() loop implementation.

---
 engine/compiler.c |  2 --
 engine/vm.c       | 33 ++++++++-------------------------
 include/ph7int.h  | 13 +++----------
 3 files changed, 11 insertions(+), 37 deletions(-)

diff --git a/engine/compiler.c b/engine/compiler.c
index 3fb00c7..6173e2f 100644
--- a/engine/compiler.c
+++ b/engine/compiler.c
@@ -1840,8 +1840,6 @@ static sxi32 PH7_CompileForeach(ph7_gen_state *pGen) {
 	}
 	/* Zero the structure */
 	SyZero(pInfo, sizeof(ph7_foreach_info));
-	/* Initialize structure fields */
-	SySetInit(&pInfo->aStep, &pGen->pVm->sAllocator, sizeof(ph7_foreach_step *));
 
 	pCur = pGen->pIn;
 	while(pCur < pEnd && (pCur->nType & PH7_TK_ARRAY_OP) == 0) {
diff --git a/engine/vm.c b/engine/vm.c
index e0ef2cf..9dfe418 100644
--- a/engine/vm.c
+++ b/engine/vm.c
@@ -4057,24 +4057,13 @@ static sxi32 VmByteCodeExec(
 						}
 						pc = pInstr->iP2 - 1;
 					} else {
-						ph7_foreach_step *pStep;
-						pStep = (ph7_foreach_step *)SyMemBackendPoolAlloc(&pVm->sAllocator, sizeof(ph7_foreach_step));
-						if(pStep == 0) {
-							PH7_VmMemoryError(&(*pVm));
-						} else {
-							/* Zero the structure */
-							SyZero(pStep, sizeof(ph7_foreach_step));
-							/* Prepare the step */
-							ph7_hashmap *pMap = (ph7_hashmap *)pTos->x.pOther;
-							/* Reset the internal loop cursor */
-							PH7_HashmapResetLoopCursor(pMap);
-							/* Mark the step */
-							pStep->xIter.pMap = pMap;
-							pMap->iRef++;
-						}
-						if(SXRET_OK != SySetPut(&pInfo->aStep, (const void *)&pStep)) {
-							PH7_VmMemoryError(&(*pVm));
-						}
+						/* Prepare the hashmap */
+						ph7_hashmap *pMap = (ph7_hashmap *)pTos->x.pOther;
+						/* Reset the internal loop cursor */
+						PH7_HashmapResetLoopCursor(pMap);
+						/* Store an array in a loop pointer */
+						pInfo->pMap = pMap;
+						pMap->iRef++;
 					}
 					VmPopOperand(&pTos, 1);
 					break;
@@ -4085,18 +4074,14 @@ static sxi32 VmByteCodeExec(
 			 */
 			case PH7_OP_FOREACH_STEP: {
 					ph7_foreach_info *pInfo = (ph7_foreach_info *)pInstr->p3;
-					ph7_foreach_step **apStep, *pStep;
 					ph7_value *pValue;
 					VmFrame *pFrame;
-					/* Peek the last step */
-					apStep = (ph7_foreach_step **)SySetBasePtr(&pInfo->aStep);
-					pStep = apStep[SySetUsed(&pInfo->aStep) - 1];
 					pFrame = pVm->pFrame;
 					while(pFrame->pParent && (pFrame->iFlags & VM_FRAME_EXCEPTION)) {
 						/* Safely ignore the exception frame */
 						pFrame = pFrame->pParent;
 					}
-					ph7_hashmap *pMap = pStep->xIter.pMap;
+					ph7_hashmap *pMap = pInfo->pMap;
 					ph7_hashmap_node *pNode;
 					/* Extract the current node value */
 					pNode = PH7_HashmapGetNextEntry(pMap);
@@ -4106,8 +4091,6 @@ static sxi32 VmByteCodeExec(
 						/* Automatically reset the loop cursor */
 						PH7_HashmapResetLoopCursor(pMap);
 						/* Cleanup the mess left behind */
-						SyMemBackendPoolFree(&pVm->sAllocator, pStep);
-						SySetPop(&pInfo->aStep);
 						PH7_HashmapUnref(pMap);
 					} else {
 						if(SyStringLength(&pInfo->sKey) > 0) {
diff --git a/include/ph7int.h b/include/ph7int.h
index c7aa980..d4bc4a3 100644
--- a/include/ph7int.h
+++ b/include/ph7int.h
@@ -789,16 +789,9 @@ struct ph7_hashmap {
 struct ph7_foreach_info {
 	SyString sKey;      /* Key name. Empty otherwise*/
 	SyString sValue;    /* Value name */
-	SySet aStep;        /* Stack of steps [i.e: ph7_foreach_step instance] */
-};
-struct ph7_foreach_step {
-	/* Iterate on those values */
-	union {
-		ph7_hashmap *pMap;          /* Hashmap [i.e: array in the PHP jargon] iteration
-									 * Ex: foreach(array(1,2,3) as $key=>$value){}
-									 */
-		ph7_class_instance *pThis;  /* Class instance [i.e: object] iteration */
-	} xIter;
+	ph7_hashmap *pMap;  /* Hashmap [i.e: array in the PHP jargon] iteration
+						 * Ex: foreach(array(1,2,3) as $key=>$value){}
+						 */
 };
 /*
  * Each PH7 engine is identified by an instance of the following structure.