Fixed a test that ensures the LocalRewriter does not attempt to
avoid reloads by reusing clobbered registers.
This was causing issues in 256.bzip2 when compiled with PIC for
a while (starting at r78217), though the problem has since been masked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80872 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h
index 1673c9a..421d0bb 100644
--- a/include/llvm/Target/TargetRegisterInfo.h
+++ b/include/llvm/Target/TargetRegisterInfo.h
@@ -386,9 +386,16 @@
return NumRegs;
}
- /// areAliases - Returns true if the two registers alias each other, false
- /// otherwise
- bool areAliases(unsigned regA, unsigned regB) const {
+ /// regsOverlap - Returns true if the two registers are equal or alias each
+ /// other. The registers may be virtual register.
+ bool regsOverlap(unsigned regA, unsigned regB) const {
+ if (regA == regB)
+ return true;
+
+ if (isVirtualRegister(regA) || isVirtualRegister(regB))
+ return false;
+
+ // regA and regB are distinct physical registers. Do they alias?
size_t index = (regA + regB * 37) & (AliasesHashSize-1);
unsigned ProbeAmt = 0;
while (AliasesHash[index*2] != 0 &&
@@ -403,17 +410,6 @@
return false;
}
- /// regsOverlap - Returns true if the two registers are equal or alias each
- /// other. The registers may be virtual register.
- bool regsOverlap(unsigned regA, unsigned regB) const {
- if (regA == regB)
- return true;
-
- if (isVirtualRegister(regA) || isVirtualRegister(regB))
- return false;
- return areAliases(regA, regB);
- }
-
/// isSubRegister - Returns true if regB is a sub-register of regA.
///
bool isSubRegister(unsigned regA, unsigned regB) const {
diff --git a/lib/CodeGen/RegAllocPBQP.cpp b/lib/CodeGen/RegAllocPBQP.cpp
index 853192c..e85a5ac 100644
--- a/lib/CodeGen/RegAllocPBQP.cpp
+++ b/lib/CodeGen/RegAllocPBQP.cpp
@@ -269,7 +269,7 @@
unsigned reg2 = *a2Itr;
// If the row/column regs are identical or alias insert an infinity.
- if ((reg1 == reg2) || tri->areAliases(reg1, reg2)) {
+ if (tri->regsOverlap(reg1, reg2)) {
(*m)[ri][ci] = std::numeric_limits<PBQP::PBQPNum>::infinity();
isZeroMatrix = false;
}
diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp
index 6da6a9b..79b366c 100644
--- a/lib/CodeGen/VirtRegRewriter.cpp
+++ b/lib/CodeGen/VirtRegRewriter.cpp
@@ -797,7 +797,7 @@
// value aliases the new register. If so, codegen the previous reload
// and use this one.
unsigned PRRU = Op.PhysRegReused;
- if (TRI->areAliases(PRRU, PhysReg)) {
+ if (TRI->regsOverlap(PRRU, PhysReg)) {
// Okay, we found out that an alias of a reused register
// was used. This isn't good because it means we have
// to undo a previous reuse.