[llvm] afdc6a0 - [Hexagon] Some compound opportunities missed in presence of branches

[Krzysztof Parzyszek via llvm-commits]

Author: Colin LeMahieu
Date: 2022-01-06T09:25:56-08:00
New Revision: afdc6a0b8eeec1a8ebe52b103ac1fdcfb93db3b3

URL: https://github.com/llvm/llvm-project/commit/afdc6a0b8eeec1a8ebe52b103ac1fdcfb93db3b3
DIFF: https://github.com/llvm/llvm-project/commit/afdc6a0b8eeec1a8ebe52b103ac1fdcfb93db3b3.diff

LOG: [Hexagon] Some compound opportunities missed in presence of branches

Added: 
    llvm/test/MC/Hexagon/bug28416.s

Modified: 
    llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCompound.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCompound.cpp b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCompound.cpp
index e7ade7834a9f..7d4828e7c66a 100644
--- a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCompound.cpp
+++ b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCompound.cpp
@@ -365,8 +365,10 @@ static bool lookForCompound(MCInstrInfo const &MCII, MCContext &Context,
                MCI.begin() + HexagonMCInstrInfo::bundleInstructionsOffset;
            B != MCI.end(); ++B) {
         MCInst const *Inst = B->getInst();
-        if (JumpInst == Inst)
+        if (JumpInst == Inst) {
+          BExtended = false;
           continue;
+        }
         if (HexagonMCInstrInfo::isImmext(*Inst)) {
           BExtended = true;
           continue;

diff  --git a/llvm/test/MC/Hexagon/bug28416.s b/llvm/test/MC/Hexagon/bug28416.s
new file mode 100644
index 000000000000..237d577a7a48
--- /dev/null
+++ b/llvm/test/MC/Hexagon/bug28416.s
@@ -0,0 +1,11 @@
+# RUN: llvm-mc -arch=hexagon -filetype=obj -o - %s | llvm-objdump -d -
+# r0 = r6 and jump ##undefined should compound to J4_jumpsetr
+
+# CHECK: { immext(#0)
+# CHECK:   r0 = r6 ; jump 0x0
+# CHECK:   r1 = memub(r6+#21)
+# CHECK:   memw(r9+#0) = r0 }
+{  memw(r9) = r0
+   r0 = r6
+   r1 = memub(r6+#21)
+   jump ##undefined }