From 1a9ead1e25587c0ce424ca3063b6c0abdb6f5328 Mon Sep 17 00:00:00 2001 From: Adam Higerd Date: Mon, 27 Jul 2020 22:06:44 -0500 Subject: [PATCH] Stack trace: use popcount function instead of inline loop --- src/arm/debugger/debugger.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/src/arm/debugger/debugger.c b/src/arm/debugger/debugger.c index 1fc4bb324..bce6a4408 100644 --- a/src/arm/debugger/debugger.c +++ b/src/arm/debugger/debugger.c @@ -12,6 +12,7 @@ #include #include #include +#include #include DEFINE_VECTOR(ARMDebugBreakpointList, struct ARMDebugBreakpoint); @@ -63,14 +64,8 @@ static bool ARMDebuggerUpdateStackTraceInternal(struct mDebuggerPlatform* d, uin // need ANOTHER stack frame, so only skip if it's not. } else if (info.operandFormat & ARM_OPERAND_MEMORY_1) { // This is most likely ldmia ..., {..., pc}, which is a function return. - // To find which stack slot holds the return address, count number of set bits. - // (gcc/clang will convert the loop to intrinsics if available) - int regCount = 0; - uint32_t reglist = info.op1.immediate; - while (reglist != 0) { - reglist &= reglist - 1; - regCount++; - } + // To find which stack slot holds the return address, count the number of set bits. + int regCount = popcount32(info.op1.immediate); uint32_t baseAddress = cpu->gprs[info.memory.baseReg] + ((regCount - 1) << 2); destAddress = cpu->memory.load32(cpu, baseAddress, NULL); } else if (info.operandFormat & ARM_OPERAND_IMMEDIATE_1) {