[PowerPC] Cleanly reject asm crbit constraint with -crbits

When crbits are disabled, cleanly reject the constraint (return the register
class only to cause an assert later).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251566 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index b1f87831860a8a06865705ce805c9f4d0b4e529d..ce6f3a6e75d2b7febe79999966307a624ba5192f 100644 (file)
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -10927,7 +10927,8 @@ PPCTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
     case 'y':   // crrc
       return std::make_pair(0U, &PPC::CRRCRegClass);
     }
-  } else if (Constraint == "wc") { // an individual CR bit.
+  } else if (Constraint == "wc" && Subtarget.useCRBits()) {
+    // An individual CR bit.
     return std::make_pair(0U, &PPC::CRBITRCRegClass);
   } else if (Constraint == "wa" || Constraint == "wd" ||
              Constraint == "wf") {

diff --git a/test/CodeGen/PowerPC/crbit-asm-disabled.ll b/test/CodeGen/PowerPC/crbit-asm-disabled.ll
new file mode 100644 (file)
index 0000000..56ec8ec
--- /dev/null
+++ b/test/CodeGen/PowerPC/crbit-asm-disabled.ll
@@ -0,0 +1,16 @@
+; RUN: not llc -mcpu=pwr7 -o /dev/null %s 2>&1 | FileCheck %s
+target datalayout = "E-m:e-i64:64-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+define zeroext i1 @testi1(i1 zeroext %b1, i1 zeroext %b2) #0 {
+entry:
+  %0 = tail call i8 asm "crand $0, $1, $2", "=^wc,^wc,^wc"(i1 %b1, i1 %b2) #0
+  %1 = and i8 %0, 1
+  %tobool3 = icmp ne i8 %1, 0
+  ret i1 %tobool3
+
+; CHECK: error: couldn't allocate output register for constraint 'wc'
+}
+
+attributes #0 = { nounwind "target-features"="-crbits" }
+