[Hexagon] Recognize potential offset overflow for store-imm to stack

Reserve an extra scavenging stack slot if the offset field in store-
-immediate instructions may overflow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306004 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/Hexagon/HexagonFrameLowering.cpp b/lib/Target/Hexagon/HexagonFrameLowering.cpp
index 18e49c69b8e36245ec601e73856e307ad53e861b..f0b7f5873797914d0e86c28e60063ff6ed175a8b 100644 (file)
--- a/lib/Target/Hexagon/HexagonFrameLowering.cpp
+++ b/lib/Target/Hexagon/HexagonFrameLowering.cpp
@@ -2454,9 +2454,44 @@ bool HexagonFrameLowering::mayOverflowFrameOffset(MachineFunction &MF) const {
   unsigned StackSize = MF.getFrameInfo().estimateStackSize(MF);
   auto &HST = MF.getSubtarget<HexagonSubtarget>();
   // A fairly simplistic guess as to whether a potential load/store to a
-  // stack location could require an extra register. It does not account
-  // for store-immediate instructions.
-  if (HST.useHVXOps())
-    return StackSize > 256;
+  // stack location could require an extra register.
+  if (HST.useHVXOps() && StackSize > 256)
+    return true;
+
+  // Check if the function has store-immediate instructions that access
+  // the stack. Since the offset field is not extendable, if the stack
+  // size exceeds the offset limit (6 bits, shifted), the stores will
+  // require a new base register.
+  bool HasImmStack = false;
+  unsigned MinLS = ~0u;   // Log_2 of the memory access size.
+
+  for (const MachineBasicBlock &B : MF) {
+    for (const MachineInstr &MI : B) {
+      unsigned LS = 0;
+      switch (MI.getOpcode()) {
+        case Hexagon::S4_storeirit_io:
+        case Hexagon::S4_storeirif_io:
+        case Hexagon::S4_storeiri_io:
+          ++LS;
+          LLVM_FALLTHROUGH;
+        case Hexagon::S4_storeirht_io:
+        case Hexagon::S4_storeirhf_io:
+        case Hexagon::S4_storeirh_io:
+          ++LS;
+          LLVM_FALLTHROUGH;
+        case Hexagon::S4_storeirbt_io:
+        case Hexagon::S4_storeirbf_io:
+        case Hexagon::S4_storeirb_io:
+          if (MI.getOperand(0).isFI())
+            HasImmStack = true;
+          MinLS = std::min(MinLS, LS);
+          break;
+      }
+    }
+  }
+
+  if (HasImmStack)
+    return !isUInt<6>(StackSize >> MinLS);
+
   return false;
 }

diff --git a/test/CodeGen/Hexagon/store-imm-large-stack.ll b/test/CodeGen/Hexagon/store-imm-large-stack.ll
new file mode 100644 (file)
index 0000000..c7e493a
--- /dev/null
+++ b/test/CodeGen/Hexagon/store-imm-large-stack.ll
@@ -0,0 +1,151 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+; Check that this testcase compiles successfully.
+; CHECK: allocframe
+
+target triple = "hexagon"
+
+@g0 = external global [1024 x i8], align 8
+@g1 = external global [1024 x i8], align 8
+@g2 = external global [1024 x i8], align 8
+@g3 = external global [1024 x i8], align 8
+@g4 = external hidden unnamed_addr constant [40 x i8], align 1
+
+; Function Attrs: nounwind
+define void @fred() local_unnamed_addr #0 {
+b0:
+  %v1 = alloca i32, align 4
+  %v2 = alloca i32, align 4
+  %v3 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 9), align 1
+  %v4 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 10), align 2
+  store i32 24, i32* %v1, align 4
+  store i8 %v3, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 16), align 8
+  store i8 %v4, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 10), align 2
+  store i32 44, i32* %v2, align 4
+  store i16 0, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 4) to i16*), align 4
+  %v5 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 11) to i16*), align 1
+  store i16 %v5, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 18) to i16*), align 2
+  %v6 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 13) to i32*), align 1
+  store i32 %v6, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 20) to i32*), align 4
+  %v7 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 17) to i16*), align 1
+  store i16 %v7, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 24) to i16*), align 8
+  %v8 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 23) to i16*), align 1
+  store i16 %v8, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 32) to i16*), align 8
+  %v9 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 25) to i32*), align 1
+  store i32 %v9, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 36) to i32*), align 4
+  %v10 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 29) to i16*), align 1
+  store i16 %v10, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 40) to i16*), align 8
+  %v11 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 31) to i32*), align 1
+  store i32 %v11, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 44) to i32*), align 4
+  %v12 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 35) to i16*), align 1
+  store i16 %v12, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 48) to i16*), align 8
+  %v13 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 37) to i32*), align 1
+  store i32 %v13, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 52) to i32*), align 4
+  %v14 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 41) to i16*), align 1
+  store i16 %v14, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 56) to i16*), align 8
+  %v15 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 43) to i32*), align 1
+  store i32 %v15, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 60) to i32*), align 4
+  %v16 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 47) to i16*), align 1
+  store i16 %v16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 64) to i16*), align 8
+  %v17 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 49) to i32*), align 1
+  store i32 %v17, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 68) to i32*), align 4
+  %v18 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 53) to i16*), align 1
+  store i16 %v18, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 72) to i16*), align 8
+  %v19 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 55) to i32*), align 1
+  store i32 %v19, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 76) to i32*), align 4
+  %v20 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 61) to i32*), align 1
+  store i32 %v20, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 84) to i32*), align 4
+  %v21 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 73) to i32*), align 1
+  store i32 %v21, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 100) to i32*), align 4
+  store i32 104, i32* %v1, align 4
+  store i8 %v4, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 10), align 2
+  store i16 %v8, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 23) to i16*), align 1
+  store i32 %v9, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 25) to i32*), align 1
+  store i16 %v10, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 29) to i16*), align 1
+  store i32 %v11, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 31) to i32*), align 1
+  store i16 %v12, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 35) to i16*), align 1
+  store i32 %v13, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 37) to i32*), align 1
+  store i16 %v14, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 41) to i16*), align 1
+  store i32 %v15, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 43) to i32*), align 1
+  store i16 %v16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 47) to i16*), align 1
+  store i32 %v17, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 49) to i32*), align 1
+  store i32 %v19, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 55) to i32*), align 1
+  store i32 %v20, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 61) to i32*), align 1
+  store i32 %v21, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 73) to i32*), align 1
+  %v22 = trunc i32 %v6 to i8
+  store i8 %v22, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 20), align 4
+  store i32 24, i32* %v1, align 4
+  store i16 0, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 4) to i16*), align 4
+  store i8 %v3, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 9), align 1
+  store i16 %v5, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 11) to i16*), align 1
+  store i8 %v22, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 13), align 1
+  store i32 14, i32* %v2, align 4
+  store i8 %v4, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 17), align 1
+  %v23 = load i64, i64* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 11) to i64*), align 1
+  store i64 %v23, i64* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 24) to i64*), align 8
+  %v24 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 19) to i16*), align 1
+  store i16 %v24, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 32) to i16*), align 8
+  %v25 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 21) to i32*), align 1
+  store i32 %v25, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 36) to i32*), align 4
+  %v26 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 25) to i32*), align 1
+  store i32 %v26, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 40) to i32*), align 8
+  %v27 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 29) to i16*), align 1
+  store i16 %v27, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 44) to i16*), align 4
+  %v28 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 31) to i16*), align 1
+  store i16 %v28, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 46) to i16*), align 2
+  %v29 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 33), align 1
+  store i8 %v29, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 48), align 8
+  %v30 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 34), align 2
+  store i8 %v30, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 56), align 8
+  %v31 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 35) to i32*), align 1
+  store i32 %v31, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 60) to i32*), align 4
+  %v32 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 39) to i32*), align 1
+  store i32 72, i32* %v1, align 4
+  store i32 0, i32* bitcast ([1024 x i8]* @g2 to i32*), align 8
+  store i16 0, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 4) to i16*), align 4
+  store i8 %v3, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 9), align 1
+  store i32 %v25, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 21) to i32*), align 1
+  store i32 %v26, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 25) to i32*), align 1
+  store i16 %v27, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 29) to i16*), align 1
+  store i16 %v28, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 31) to i16*), align 1
+  store i8 %v29, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 33), align 1
+  store i8 %v30, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 34), align 2
+  store i32 %v31, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 35) to i32*), align 1
+  store i32 %v32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 39) to i32*), align 1
+  store i32 43, i32* %v2, align 4
+  %v33 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g1, i32 0, i32 0), align 8
+  %v34 = zext i8 %v33 to i32
+  tail call void (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @g4, i32 0, i32 0), i32 %v34, i32 0) #0
+  %v35 = load i8, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 7), align 1
+  store i8 %v35, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 7), align 1
+  %v36 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 17) to i16*), align 1
+  store i16 %v36, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 24) to i16*), align 8
+  %v37 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 19) to i32*), align 1
+  %v38 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 31) to i32*), align 1
+  store i32 %v38, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 44) to i32*), align 4
+  %v39 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 35) to i16*), align 1
+  %v40 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 37) to i32*), align 1
+  store i32 %v40, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 52) to i32*), align 4
+  %v41 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 43) to i32*), align 1
+  store i32 %v41, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 60) to i32*), align 4
+  %v42 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 47) to i16*), align 1
+  store i16 %v42, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 64) to i16*), align 8
+  %v43 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 49) to i32*), align 1
+  store i32 %v43, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 68) to i32*), align 4
+  %v44 = load i16, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 59) to i16*), align 1
+  store i16 %v44, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 80) to i16*), align 8
+  %v45 = load i32, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g0, i32 0, i32 67) to i32*), align 1
+  store i32 %v45, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g3, i32 0, i32 92) to i32*), align 4
+  store i32 96, i32* %v1, align 4
+  store i8 %v35, i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 7), align 1
+  store i16 %v36, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 17) to i16*), align 1
+  store i32 %v37, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 19) to i32*), align 1
+  store i32 %v38, i32* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 31) to i32*), align 1
+  store i16 %v39, i16* bitcast (i8* getelementptr inbounds ([1024 x i8], [1024 x i8]* @g2, i32 0, i32 35) to i16*), align 1
+  call void (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @g4, i32 0, i32 0), i32 0, i32 0) #0
+  call void (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @g4, i32 0, i32 0), i32 undef, i32 0) #0
+  unreachable
+}
+
+declare void @printf(i8* nocapture readonly, ...) local_unnamed_addr #0
+
+attributes #0 = { nounwind "target-cpu"="hexagonv5" }