d1a838babc
Basic block sections enables function sections implicitly, this is not needed and is inefficient with "=list" option. We had basic block sections enable function sections implicitly in clang. This is particularly inefficient with "=list" option as it places functions that do not have any basic block sections in separate sections. This causes unnecessary object file overhead for large applications. This patch disables this implicit behavior. It only creates function sections for those functions that require basic block sections. Further, there was an inconistent behavior with llc as llc was not turning on function sections by default. This patch makes llc and clang consistent and tests are added to check the new behavior. This is the first of two patches and this adds functionality in LLVM to create a new section for the entry block if function sections is not enabled. Differential Revision: https://reviews.llvm.org/D93876
19 lines
785 B
LLVM
19 lines
785 B
LLVM
; Check that basic block section is emitted when a non-entry block has no predecessors.
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; RUN: llc < %s -mtriple=x86_64 -O0 -basic-block-sections=all | FileCheck %s --check-prefix=CHECK-SECTIONS
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; RUN: llc < %s -mtriple=x86_64 -O0 | FileCheck %s --check-prefix=CHECK-NOSECTIONS
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define void @foo(i32* %bar) {
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%v = load i32, i32* %bar
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switch i32 %v, label %default [
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i32 0, label %target
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]
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target:
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ret void
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;; This is the block which will not have any predecessors. If the block is not garbage collected, it must
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;; be placed in a basic block section with a corresponding symbol.
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default:
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unreachable
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; CHECK-NOSECTIONS: # %bb.2: # %default
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; CHECK-SECTIONS: .section .text.foo,"ax",@progbits,unique,2
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; CHECK-SECTIONS-NEXT: foo.__part.2: # %default
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}
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