bc78c09952
Introduces a string attribute, amdgpu-requires-module-lds, to allow eliding the module.lds block from kernels. Will allocate the block as before if the attribute is missing or has its default value of true. Patch uses the new attribute to detect the simplest possible instance of this, where a kernel makes no calls and thus cannot call any functions that use LDS. Tests updated to match, coverage was already good. Interesting cases is in lower-module-lds-offsets where annotating the kernel allows the backend to pick a different (in this case better) variable ordering than previously. A later patch will avoid moving kernel variables into module.lds when the kernel can have this attribute, allowing optimal ordering and locally unused variable elimination. Reviewed By: arsenm Differential Revision: https://reviews.llvm.org/D122091
62 lines
4.8 KiB
LLVM
62 lines
4.8 KiB
LLVM
; RUN: opt -S -mtriple=amdgcn-- -amdgpu-lower-module-lds < %s | FileCheck %s
|
|
; RUN: opt -S -mtriple=amdgcn-- -passes=amdgpu-lower-module-lds < %s | FileCheck %s
|
|
|
|
; CHECK: %llvm.amdgcn.module.lds.t = type { float, float }
|
|
|
|
@func = addrspace(3) global float undef, align 4
|
|
|
|
; CHECK: %llvm.amdgcn.kernel.timestwo.lds.t = type { float }
|
|
|
|
@kern = addrspace(3) global float undef, align 4
|
|
|
|
; @func is only used from a non-kernel function so is rewritten
|
|
; CHECK-NOT: @func
|
|
; @both is used from a non-kernel function so is rewritten
|
|
; CHECK-NOT: @both
|
|
; sorted both < func, so @both at null and @func at 4
|
|
@both = addrspace(3) global float undef, align 4
|
|
|
|
; CHECK: @llvm.amdgcn.module.lds = internal addrspace(3) global %llvm.amdgcn.module.lds.t undef, align 4
|
|
; CHECK: @llvm.amdgcn.kernel.timestwo.lds = internal addrspace(3) global %llvm.amdgcn.kernel.timestwo.lds.t undef, align 4
|
|
|
|
; CHECK-LABEL: @get_func()
|
|
; CHECK: %0 = load i32, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
define i32 @get_func() local_unnamed_addr #0 {
|
|
entry:
|
|
%0 = load i32, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @func to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @func to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
ret i32 %0
|
|
}
|
|
|
|
; CHECK-LABEL: @set_func(i32 %x)
|
|
; CHECK: store i32 %x, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
define void @set_func(i32 %x) local_unnamed_addr #1 {
|
|
entry:
|
|
store i32 %x, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @both to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @both to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
ret void
|
|
}
|
|
|
|
; CHECK-LABEL: @timestwo() #0
|
|
; CHECK-NOT: call void @llvm.donothing()
|
|
; CHECK: %1 = bitcast float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.timestwo.lds.t, %llvm.amdgcn.kernel.timestwo.lds.t addrspace(3)* @llvm.amdgcn.kernel.timestwo.lds, i32 0, i32 0) to i32 addrspace(3)*
|
|
; CHECK: %2 = addrspacecast i32 addrspace(3)* %1 to i32*
|
|
; CHECK: %3 = ptrtoint i32* %2 to i64
|
|
; CHECK: %4 = add i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i32 addrspace(3)*) to i32*) to i64), %3
|
|
; CHECK: %5 = inttoptr i64 %4 to i32*
|
|
; CHECK: %ld = load i32, i32* %5, align 4
|
|
; CHECK: %mul = mul i32 %ld, 2
|
|
; CHECK: %6 = bitcast float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.timestwo.lds.t, %llvm.amdgcn.kernel.timestwo.lds.t addrspace(3)* @llvm.amdgcn.kernel.timestwo.lds, i32 0, i32 0) to i32 addrspace(3)*
|
|
; CHECK: %7 = addrspacecast i32 addrspace(3)* %6 to i32*
|
|
; CHECK: %8 = ptrtoint i32* %7 to i64
|
|
; CHECK: %9 = add i64 %8, ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i32 addrspace(3)*) to i32*) to i64)
|
|
; CHECK: %10 = inttoptr i64 %9 to i32*
|
|
; CHECK: store i32 %mul, i32* %10, align 4
|
|
define amdgpu_kernel void @timestwo() {
|
|
%ld = load i32, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @both to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @kern to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
%mul = mul i32 %ld, 2
|
|
store i32 %mul, i32* inttoptr (i64 add (i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @kern to i32 addrspace(3)*) to i32*) to i64), i64 ptrtoint (i32* addrspacecast (i32 addrspace(3)* bitcast (float addrspace(3)* @both to i32 addrspace(3)*) to i32*) to i64)) to i32*), align 4
|
|
ret void
|
|
}
|
|
|
|
attributes #0 = { "amdgpu-elide-module-lds" }
|
|
; CHECK: attributes #0 = { "amdgpu-elide-module-lds" }
|