mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-04 21:30:49 +00:00
784f333aef
by the SRoA "promote to large integer" code, eliminating
some type conversions like this:
%94 = zext i16 %93 to i32 ; <i32> [#uses=2]
%96 = lshr i32 %94, 8 ; <i32> [#uses=1]
%101 = trunc i32 %96 to i8 ; <i8> [#uses=1]
This also unblocks other xforms from happening, now clang is able to compile:
struct S { float A, B, C, D; };
float foo(struct S A) { return A.A + A.B+A.C+A.D; }
into:
_foo: ## @foo
## BB#0: ## %entry
pshufd $1, %xmm0, %xmm2
addss %xmm0, %xmm2
movdqa %xmm1, %xmm3
addss %xmm2, %xmm3
pshufd $1, %xmm1, %xmm0
addss %xmm3, %xmm0
ret
on x86-64, instead of:
_foo: ## @foo
## BB#0: ## %entry
movd %xmm0, %rax
shrq $32, %rax
movd %eax, %xmm2
addss %xmm0, %xmm2
movapd %xmm1, %xmm3
addss %xmm2, %xmm3
movd %xmm1, %rax
shrq $32, %rax
movd %eax, %xmm0
addss %xmm3, %xmm0
ret
This seems pretty close to optimal to me, at least without
using horizontal adds. This also triggers in lots of other
code, including SPEC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112278 91177308-0d34-0410-b5e6-96231b3b80d8
82 lines
1.7 KiB
LLVM
82 lines
1.7 KiB
LLVM
; RUN: opt < %s -instcombine -S | FileCheck %s
|
|
|
|
; Instcombine should be able to eliminate all of these ext casts.
|
|
|
|
declare void @use(i32)
|
|
|
|
define i64 @test1(i64 %a) {
|
|
%b = trunc i64 %a to i32
|
|
%c = and i32 %b, 15
|
|
%d = zext i32 %c to i64
|
|
call void @use(i32 %b)
|
|
ret i64 %d
|
|
; CHECK: @test1
|
|
; CHECK: %d = and i64 %a, 15
|
|
; CHECK: ret i64 %d
|
|
}
|
|
define i64 @test2(i64 %a) {
|
|
%b = trunc i64 %a to i32
|
|
%c = shl i32 %b, 4
|
|
%q = ashr i32 %c, 4
|
|
%d = sext i32 %q to i64
|
|
call void @use(i32 %b)
|
|
ret i64 %d
|
|
; CHECK: @test2
|
|
; CHECK: shl i64 %a, 36
|
|
; CHECK: %d = ashr i64 {{.*}}, 36
|
|
; CHECK: ret i64 %d
|
|
}
|
|
define i64 @test3(i64 %a) {
|
|
%b = trunc i64 %a to i32
|
|
%c = and i32 %b, 8
|
|
%d = zext i32 %c to i64
|
|
call void @use(i32 %b)
|
|
ret i64 %d
|
|
; CHECK: @test3
|
|
; CHECK: %d = and i64 %a, 8
|
|
; CHECK: ret i64 %d
|
|
}
|
|
define i64 @test4(i64 %a) {
|
|
%b = trunc i64 %a to i32
|
|
%c = and i32 %b, 8
|
|
%x = xor i32 %c, 8
|
|
%d = zext i32 %x to i64
|
|
call void @use(i32 %b)
|
|
ret i64 %d
|
|
; CHECK: @test4
|
|
; CHECK: = and i64 %a, 8
|
|
; CHECK: %d = xor i64 {{.*}}, 8
|
|
; CHECK: ret i64 %d
|
|
}
|
|
|
|
define i32 @test5(i32 %A) {
|
|
%B = zext i32 %A to i128
|
|
%C = lshr i128 %B, 16
|
|
%D = trunc i128 %C to i32
|
|
ret i32 %D
|
|
; CHECK: @test5
|
|
; CHECK: %C = lshr i32 %A, 16
|
|
; CHECK: ret i32 %C
|
|
}
|
|
|
|
define i32 @test6(i64 %A) {
|
|
%B = zext i64 %A to i128
|
|
%C = lshr i128 %B, 32
|
|
%D = trunc i128 %C to i32
|
|
ret i32 %D
|
|
; CHECK: @test6
|
|
; CHECK: %C = lshr i64 %A, 32
|
|
; CHECK: %D = trunc i64 %C to i32
|
|
; CHECK: ret i32 %D
|
|
}
|
|
|
|
define i92 @test7(i64 %A) {
|
|
%B = zext i64 %A to i128
|
|
%C = lshr i128 %B, 32
|
|
%D = trunc i128 %C to i92
|
|
ret i92 %D
|
|
; CHECK: @test7
|
|
; CHECK: %C = lshr i64 %A, 32
|
|
; CHECK: %D = zext i64 %C to i92
|
|
; CHECK: ret i92 %D
|
|
} |