[RyuJIT/ARM32] Use 'subs' instead of 'sub' on localloc

Previous implementation used sub instruction for counter
conditional execution for iterating over loops which cause incorrect
behavior.

diff --git a/src/jit/codegenarm.cpp b/src/jit/codegenarm.cpp
index 4507a5c1404b38f7a459e7255c4e702d50ea8566..bac24d578483559457ec016aa23d245ee64c3a27 100644 (file)
--- a/src/jit/codegenarm.cpp
+++ b/src/jit/codegenarm.cpp
@@ -1267,7 +1267,7 @@ void CodeGen::genLclHeap(GenTreePtr tree)
         // If not done, loop
         // Note that regCnt is the number of bytes to stack allocate.
         assert(genIsValidIntReg(regCnt));
-        getEmitter()->emitIns_R_R_I(INS_sub, EA_PTRSIZE, regCnt, regCnt, STACK_ALIGN);
+        getEmitter()->emitIns_R_I(INS_sub, EA_PTRSIZE, regCnt, STACK_ALIGN, INS_FLAGS_SET);
         emitJumpKind jmpNotEqual = genJumpKindForOper(GT_NE, CK_SIGNED);
         inst_JMP(jmpNotEqual, loop);
     }
@@ -1311,7 +1311,7 @@ void CodeGen::genLclHeap(GenTreePtr tree)
         BasicBlock* done = genCreateTempLabel();
 
         //       subs  regCnt, SP, regCnt      // regCnt now holds ultimate SP
-        getEmitter()->emitIns_R_R_R(INS_sub, EA_PTRSIZE, regCnt, REG_SPBASE, regCnt);
+        getEmitter()->emitIns_R_R_R(INS_sub, EA_PTRSIZE, regCnt, REG_SPBASE, regCnt, INS_FLAGS_SET);
 
         inst_JMP(EJ_vc, loop); // branch if the V flag is not set