commit 18bb769850528ebe76486b252adb662647fc2111
parent 9d56e2c7adbf9b74fbed4437931324a39b56d349
Author: André Bargull <andre.bargull@gmail.com>
Date: Fri, 17 Oct 2025 11:25:45 +0000
Bug 1994191 - Part 3: Add branch float helpers to request short jumps. r=spidermonkey-reviewers,iain
This avoids code duplication.
Differential Revision: https://phabricator.services.mozilla.com/D268552
Diffstat:
4 files changed, 40 insertions(+), 73 deletions(-)
diff --git a/js/src/jit/riscv64/CodeGenerator-riscv64.cpp b/js/src/jit/riscv64/CodeGenerator-riscv64.cpp
@@ -1527,18 +1527,14 @@ void CodeGenerator::visitPowHalfD(LPowHalfD* ins) {
// Masm.pow(-Infinity, 0.5) == Infinity.
masm.loadConstantDouble(NegativeInfinity<double>(), fpscratch);
- UseScratchRegisterScope temps(&masm);
- Register scratch = temps.Acquire();
-
- masm.ma_compareF64(scratch, Assembler::DoubleNotEqualOrUnordered, input,
- fpscratch);
- masm.ma_b(scratch, Imm32(0), &skip, Assembler::NotEqual, ShortJump);
- // masm.ma_bc_d(input, fpscratch, &skip, Assembler::DoubleNotEqualOrUnordered,
- // ShortJump);
- masm.fneg_d(output, fpscratch);
- masm.ma_branch(&done, ShortJump);
-
+ masm.BranchFloat64(Assembler::DoubleNotEqualOrUnordered, input, fpscratch,
+ &skip, ShortJump);
+ {
+ masm.fneg_d(output, fpscratch);
+ masm.ma_branch(&done, ShortJump);
+ }
masm.bind(&skip);
+
// Math.pow(-0, 0.5) == 0 == Math.pow(0, 0.5).
// Adding 0 converts any -0 to 0.
masm.loadConstantDouble(0.0, fpscratch);
diff --git a/js/src/jit/riscv64/MacroAssembler-riscv64-inl.h b/js/src/jit/riscv64/MacroAssembler-riscv64-inl.h
@@ -649,18 +649,13 @@ void MacroAssembler::branch64(Condition cond, const Address& lhs,
void MacroAssembler::branchDouble(DoubleCondition cc, FloatRegister frs1,
FloatRegister frs2, Label* L) {
- UseScratchRegisterScope temps(this);
- Register scratch = temps.Acquire();
- ma_compareF64(scratch, cc, frs1, frs2);
- ma_b(scratch, Imm32(0), L, NotEqual);
+ BranchFloat64(cc, frs1, frs2, L, LongJump);
}
void MacroAssembler::branchFloat(DoubleCondition cc, FloatRegister frs1,
FloatRegister frs2, Label* L) {
- UseScratchRegisterScope temps(this);
- Register scratch = temps.Acquire();
- ma_compareF32(scratch, cc, frs1, frs2);
- ma_b(scratch, Imm32(0), L, NotEqual);
+ BranchFloat32(cc, frs1, frs2, L, LongJump);
}
+
void MacroAssembler::branchMulPtr(Condition cond, Register src, Register dest,
Label* label) {
MOZ_ASSERT(cond == Assembler::Overflow);
diff --git a/js/src/jit/riscv64/MacroAssembler-riscv64.cpp b/js/src/jit/riscv64/MacroAssembler-riscv64.cpp
@@ -4052,12 +4052,8 @@ void MacroAssembler::roundFloat32ToInt32(FloatRegister src, Register dest,
// Branch to a slow path if input < 0.0 due to complicated rounding rules.
{
- UseScratchRegisterScope temps(this);
- Register scratch = temps.Acquire();
-
- fmv_w_x(temp, zero);
- ma_compareF32(scratch, Assembler::DoubleLessThan, src, temp);
- ma_b(scratch, Imm32(0), &negative, Assembler::NotEqual, ShortJump);
+ loadConstantFloat32(0.0f, temp);
+ BranchFloat32(Assembler::DoubleLessThan, src, temp, &negative, ShortJump);
}
// Fail if the input is negative zero.
@@ -4118,12 +4114,8 @@ void MacroAssembler::roundDoubleToInt32(FloatRegister src, Register dest,
// Branch to a slow path if input < 0.0 due to complicated rounding rules.
{
- UseScratchRegisterScope temps(this);
- Register scratch = temps.Acquire();
-
- fmv_d_x(temp, zero);
- ma_compareF64(scratch, Assembler::DoubleLessThan, src, temp);
- ma_b(scratch, Imm32(0), &negative, Assembler::NotEqual, ShortJump);
+ loadConstantDouble(0.0, temp);
+ BranchFloat64(Assembler::DoubleLessThan, src, temp, &negative, ShortJump);
}
// Fail if the input is negative zero.
@@ -6300,6 +6292,26 @@ void MacroAssemblerRiscv64::CompareIsNanF64(Register rd, FPURegister cmp1,
ma_xor(rd, rd, Operand(1)); // rd <- isNan(cmp1) || isNan(cmp2)
}
+void MacroAssemblerRiscv64::BranchFloat32(DoubleCondition cc,
+ FloatRegister frs1,
+ FloatRegister frs2, Label* L,
+ JumpKind jumpKind) {
+ UseScratchRegisterScope temps(this);
+ Register scratch = temps.Acquire();
+ ma_compareF32(scratch, cc, frs1, frs2);
+ ma_b(scratch, Imm32(0), L, NotEqual, jumpKind);
+}
+
+void MacroAssemblerRiscv64::BranchFloat64(DoubleCondition cc,
+ FloatRegister frs1,
+ FloatRegister frs2, Label* L,
+ JumpKind jumpKind) {
+ UseScratchRegisterScope temps(this);
+ Register scratch = temps.Acquire();
+ ma_compareF64(scratch, cc, frs1, frs2);
+ ma_b(scratch, Imm32(0), L, NotEqual, jumpKind);
+}
+
void MacroAssemblerRiscv64::Clz32(Register rd, Register xx) {
// 32 bit unsigned in lower word: count number of leading zeros.
// int n = 32;
@@ -6746,14 +6758,11 @@ void MacroAssemblerRiscv64::FloatMinMaxHelper(FPURegister dst, FPURegister src1,
// operand is NaN; but for JS, if any operand is NaN, result is Nan. The
// following handles the discrepency between handling of NaN between ISA and
// JS semantics
- UseScratchRegisterScope temps(this);
- Register scratch = temps.Acquire();
if (std::is_same<float, F_TYPE>::value) {
- CompareIsNotNanF32(scratch, src1, src2);
+ BranchFloat32(Assembler::DoubleUnordered, src1, src2, &nan, ShortJump);
} else {
- CompareIsNotNanF64(scratch, src1, src2);
+ BranchFloat64(Assembler::DoubleUnordered, src1, src2, &nan, ShortJump);
}
- BranchFalseF(scratch, &nan);
if (kind == MaxMinKind::kMax) {
if (std::is_same<float, F_TYPE>::value) {
@@ -6805,38 +6814,6 @@ void MacroAssemblerRiscv64::Float64Min(FPURegister dst, FPURegister src1,
FloatMinMaxHelper<double>(dst, src1, src2, MaxMinKind::kMin);
}
-void MacroAssemblerRiscv64::BranchTrueShortF(Register rs, Label* target) {
- ma_branch(target, NotEqual, rs, Operand(zero_reg));
-}
-
-void MacroAssemblerRiscv64::BranchFalseShortF(Register rs, Label* target) {
- ma_branch(target, Equal, rs, Operand(zero_reg));
-}
-
-void MacroAssemblerRiscv64::BranchTrueF(Register rs, Label* target) {
- bool long_branch = target->bound() ? !is_near(target) : false;
- if (long_branch) {
- Label skip;
- BranchFalseShortF(rs, &skip);
- BranchLong(target);
- bind(&skip);
- } else {
- BranchTrueShortF(rs, target);
- }
-}
-
-void MacroAssemblerRiscv64::BranchFalseF(Register rs, Label* target) {
- bool long_branch = target->bound() ? !is_near(target) : false;
- if (long_branch) {
- Label skip;
- BranchTrueShortF(rs, &skip);
- BranchLong(target);
- bind(&skip);
- } else {
- BranchFalseShortF(rs, target);
- }
-}
-
void MacroAssemblerRiscv64::Ror(Register rd, Register rs, const Operand& rt) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
diff --git a/js/src/jit/riscv64/MacroAssembler-riscv64.h b/js/src/jit/riscv64/MacroAssembler-riscv64.h
@@ -415,11 +415,10 @@ class MacroAssemblerRiscv64 : public Assembler {
void BranchLong(Label* L);
// Floating point branches
- void BranchTrueShortF(Register rs, Label* target);
- void BranchFalseShortF(Register rs, Label* target);
-
- void BranchTrueF(Register rs, Label* target);
- void BranchFalseF(Register rs, Label* target);
+ void BranchFloat32(DoubleCondition cc, FloatRegister frs1, FloatRegister frs2,
+ Label* label, JumpKind jumpKind);
+ void BranchFloat64(DoubleCondition cc, FloatRegister frs1, FloatRegister frs2,
+ Label* label, JumpKind jumpKind);
void moveFromDoubleHi(FloatRegister src, Register dest) {
fmv_x_d(dest, src);
