Subzero: Also dump live-end info for stack vars under -asm-verbose.
It's sometimes useful to know whether a use of a stack variable (as opposed to a physical register) is the last use of that variable. For example, in a code sequence like:
movl %edx, 24(%esp)
movl 24(%esp), %edx
it would be nice to know whether the code sequence is merely bad (i.e., 24(%esp) will be used later), or horrible (i.e., this ends 24(%esp)'s live range).
We add stack variables to the per-instruction live-range-end annotation, but not to the per-block live-in and live-out annotations, because the latter would clutter the output greatly while adding very little actionable information.
BUG= https://code.google.com/p/nativeclient/issues/detail?id=4135
R=jvoung@chromium.org
Review URL: https://codereview.chromium.org/1113133002
diff --git a/src/IceCfgNode.cpp b/src/IceCfgNode.cpp
index b5e9d86..a9b34fc 100644
--- a/src/IceCfgNode.cpp
+++ b/src/IceCfgNode.cpp
@@ -824,15 +824,14 @@
SizeT NumVars = Src->getNumVars();
for (SizeT J = 0; J < NumVars; ++J) {
const Variable *Var = Src->getVar(J);
- if (Var->hasReg()) {
- if (Instr->isLastUse(Var) && --LiveRegCount[Var->getRegNum()] == 0) {
- if (First)
- Str << " \t# END=";
- else
- Str << ",";
- Var->emit(Func);
- First = false;
- }
+ if (Instr->isLastUse(Var) &&
+ (!Var->hasReg() || --LiveRegCount[Var->getRegNum()] == 0)) {
+ if (First)
+ Str << " \t# END=";
+ else
+ Str << ",";
+ Var->emit(Func);
+ First = false;
}
}
}
@@ -870,8 +869,10 @@
Liveness && Func->getContext()->getFlags().getDecorateAsm();
Str << getAsmName() << ":\n";
std::vector<SizeT> LiveRegCount(Func->getTarget()->getNumRegisters());
- if (DecorateAsm)
- emitRegisterUsage(Str, Func, this, true, LiveRegCount);
+ if (DecorateAsm) {
+ const bool IsLiveIn = true;
+ emitRegisterUsage(Str, Func, this, IsLiveIn, LiveRegCount);
+ }
for (const Inst &I : Phis) {
if (I.isDeleted())
@@ -894,8 +895,10 @@
Str << "\n";
updateStats(Func, &I);
}
- if (DecorateAsm)
- emitRegisterUsage(Str, Func, this, false, LiveRegCount);
+ if (DecorateAsm) {
+ const bool IsLiveIn = false;
+ emitRegisterUsage(Str, Func, this, IsLiveIn, LiveRegCount);
+ }
}
// Helper class for emitIAS().
