[llvm] 5603ed6 - [RISCV] Fix StackOffset calculation when using sp to access the fixed stack object in the case of rvv vector objects existed

[via llvm-commits]

Author: luxufan
Date: 2021-04-30T11:02:38+08:00
New Revision: 5603ed60ad6cd6370010e0746faef9f823c1fa72

URL: https://github.com/llvm/llvm-project/commit/5603ed60ad6cd6370010e0746faef9f823c1fa72
DIFF: https://github.com/llvm/llvm-project/commit/5603ed60ad6cd6370010e0746faef9f823c1fa72.diff

LOG: [RISCV] Fix StackOffset calculation when using sp to access the fixed stack object in the case of rvv vector objects existed

When rvv vector objects existed, using sp to access the fixed stack object will pass the rvv vector objects field. So the StackOffset needs add a scalable offset of the size of rvv vector objects field

Differential Revision: https://reviews.llvm.org/D100286

Added: 
    

Modified: 
    llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
    llvm/test/CodeGen/RISCV/rvv/localvar.ll

Removed: 
    


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diff  --git a/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp b/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
index 8ad11ae2a0bd1..f1fd9212fb334 100644
--- a/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
@@ -749,9 +749,12 @@ RISCVFrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,
       // RVV->getRVVPadding() and it can be zero. It allows us to align the RVV
       // objects to 8 bytes.
       if (MFI.getStackID(FI) == TargetStackID::Default) {
-        Offset += StackOffset::getFixed(MFI.getStackSize());
-        if (FI < 0)
-          Offset += StackOffset::getFixed(RVFI->getLibCallStackSize());
+        if (MFI.isFixedObjectIndex(FI)) {
+          Offset += StackOffset::get(MFI.getStackSize() + RVFI->getRVVPadding() 
+                        + RVFI->getLibCallStackSize(), RVFI->getRVVStackSize());
+        } else {
+          Offset += StackOffset::getFixed(MFI.getStackSize());
+        }
       } else if (MFI.getStackID(FI) == TargetStackID::ScalableVector) {
         Offset += StackOffset::get(
             alignTo(MFI.getStackSize() - RVFI->getCalleeSavedStackSize(), 8),

diff  --git a/llvm/test/CodeGen/RISCV/rvv/localvar.ll b/llvm/test/CodeGen/RISCV/rvv/localvar.ll
index 6b952496dc803..4368eec329429 100644
--- a/llvm/test/CodeGen/RISCV/rvv/localvar.ll
+++ b/llvm/test/CodeGen/RISCV/rvv/localvar.ll
@@ -294,7 +294,10 @@ define i64 @fixed_object(i64 %0, i64 %1, i64 %2, i64 %3, i64 %4, i64 %5, i64 %6,
 ; RV64IV-NEXT:    csrr a0, vlenb
 ; RV64IV-NEXT:    slli a0, a0, 3
 ; RV64IV-NEXT:    sub sp, sp, a0
-; RV64IV-NEXT:    ld a0, 32(sp)
+; RV64IV-NEXT:    csrr a0, vlenb
+; RV64IV-NEXT:    slli a0, a0, 3
+; RV64IV-NEXT:    add a0, sp, a0
+; RV64IV-NEXT:    ld a0, 32(a0)
 ; RV64IV-NEXT:    csrr a1, vlenb
 ; RV64IV-NEXT:    slli a1, a1, 3
 ; RV64IV-NEXT:    add sp, sp, a1