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[ShrinkWrap] Consider constant pool access as non-stack access #164393

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Merged
merged 4 commits into from
Oct 22, 2025
Merged

[ShrinkWrap] Consider constant pool access as non-stack access #164393

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b440b4a
[ShrinkWrap][NFC] Test with load from constant pool preventing shrink
sushgokh Oct 21, 2025
2ae1661
[ShrinkWrap] Consider constant pool access as non-stack access
sushgokh Oct 21, 2025
b377d78
address comments
sushgokh Oct 22, 2025
7807607
Merge branch 'main' into features/sgokhale/constpool-shrinwrap
sushgokh Oct 22, 2025
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2 changes: 1 addition & 1 deletion llvm/lib/CodeGen/ShrinkWrap.cpp
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Expand Up @@ -319,7 +319,7 @@ bool ShrinkWrapImpl::useOrDefCSROrFI(const MachineInstr &MI, RegScavenger *RS,
return isa<GlobalValue>(UO);
}
if (const PseudoSourceValue *PSV = Op->getPseudoValue())
return PSV->isJumpTable();
return PSV->isJumpTable() || PSV->isConstantPool();
return false;
};
// Load/store operations may access the stack indirectly when we previously
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10 changes: 6 additions & 4 deletions llvm/test/CodeGen/AArch64/shrink-wrap-const-pool-access.mir
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Expand Up @@ -21,12 +21,14 @@
br label %common.ret
}
...
# FIXME: Following code has a load from constant pool. Accessing constant pool
# Following code has a load from constant pool. Accessing constant pool
# must not be considered as a stack access and hence, shrink wrapping must
# happen.
# CHECK-LABEL:name: shrink_wrap_load_from_const_pool
# CHECK-NOT: savePoint
# CHECK-NOT: restorePoint
# CHECK-LABEL:name: shrink_wrap_load_from_const_pool
# CHECK: savePoint:
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anchor with a CHECK-LABEL?

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# CHECK: savePoint:
# CHECK-LABEL: name: shrink_wrap_load_from_const_pool
# CHECK: savePoint:

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sure, will add this before committing. Thanks

# CHECK: - point: '%bb.3'
# CHECK: restorePoint:
# CHECK: - point: '%bb.5'
---
name: shrink_wrap_load_from_const_pool
tracksRegLiveness: true
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6 changes: 3 additions & 3 deletions llvm/test/CodeGen/X86/fp128-select.ll
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Expand Up @@ -13,8 +13,8 @@ define void @test_select(ptr %p, ptr %q, i1 zeroext %c) nounwind {
; SSE: # %bb.0:
; SSE-NEXT: testl %edx, %edx
; SSE-NEXT: jne .LBB0_1
; SSE-NEXT: # %bb.3:
; SSE-NEXT: movaps {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0
; SSE-NEXT: # %bb.2:
; SSE-NEXT: movaps {{.*#+}} xmm0 = [NaN]
; SSE-NEXT: movaps %xmm0, (%rsi)
; SSE-NEXT: retq
; SSE-NEXT: .LBB0_1:
Expand Down Expand Up @@ -58,7 +58,7 @@ define fp128 @test_select_cc(fp128, fp128) nounwind {
; SSE-NEXT: xorps %xmm1, %xmm1
; SSE-NEXT: jmp .LBB1_3
; SSE-NEXT: .LBB1_1:
; SSE-NEXT: movaps {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm1
; SSE-NEXT: movaps {{.*#+}} xmm1 = [1.0E+0]
; SSE-NEXT: .LBB1_3: # %BB0
; SSE-NEXT: testl %ebx, %ebx
; SSE-NEXT: movaps (%rsp), %xmm0 # 16-byte Reload
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